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DEPARTMENTS/DÉPARTEMENTS254 President’s Cornerby Rajiv Gupta256 Editorialby Michael Attas257 News Notes / En manchettesGemini Surprise At Epsilon Indi; SCUBA-2 A Go; GRBInduced Mass Extinction; Early Chinese EclipseRecords: A Second Look257 Correspondence / CorrespondanceErratum270 From the Past / Au fil des ansFalling Stars296 Reviews / CritiquesSolar Sytem Voyage, by Serge Brunier; The Bible andAstronomy: The Magi and the Star in the Gospel, byGustav Teres, S.J.; Parallax: The Race to Measure theCosmos, by Alan W. Hirshfeld; The Big Splat, or Howthe Moon Came to Be, by Dana McKenzie301 Index to Volume 97, 2003Book Reviewsp. 296News Notesp. 257ACROSS THE RASCDU NOUVEAU DANS LES CENTRES281 Society News/Nouvelles de la sociétéby Kim Hay282 International Astronomy Day 2004 is SaturdayApril 24by Bruce McCurdy291 Observation of the 1761 Transit of Venusfrom St. John’s Newfoundlandby Frederick R. Smith294 Edmonton’s Amazing Marzathon 2003by Sherrilyn JahrigCover:Newtonian Opticksp. 266Photo: Royal MailAstroCrypticAnswersp. 293December/ décembre 2003 JRASC253

President’s Cornerby Rajiv Gupta (rgupta@telus.net)As many of you know, 2003 has been aspecial year for the Society, as it hasmarked the 100th anniversary of ourRoyal charter. The celebration of our RoyalCentenary has been an ongoing source of pridefor me for about a year now, ever since thecelebration kicked off personally for me onOctober 7, 2003 when I represented the RASC at a functionattended by Her Majesty Queen Elizabeth II. I celebrated duringmy extensive travels to the Centres in the fall of 2002 andwinter/spring of 2003. And, the celebration continued well intothe summer of 2003, when another regal woman, The HonourableIona Campanoglo, Lieutenant Governor of British Columbia,graced us with her presence at the 2003 General Assembly inVancouver.But, I’ve been keeping some secret news within me forover three months that elevates our special year to yet anotherlevel of celebration. I learned this wonderful news on June 26,shortly before the commencement of the 2003 GA, in the formof a telephone call from Dr. Tom Brzustowski, president ofNSERC, Canada’s major scientific granting agency. He informedme that the RASC was one of 5 recipients of a 2003 MichaelSmith Award for Science Promotion, out of approximately 25nominations submitted to NSERC. While I shared the newswith the RASC Executive and the three RASC members mostlyresponsible for the nomination, James Edgar, John Percy, andRoland Dechesne, I could not inform our members at large untilthe official ministerial announcement, which is scheduled formid-November. I was dying to announce the award at the 2003GA, and can finally inform all of you in this column, which willappear only after the official announcement by the Canadiangovernment.I’ll travel to an awards ceremony in Ottawa on November19 to receive the Society’s medal and a framed citation, whichwill be proudly displayed at our Toronto office. The Society hasalready received a $10,000 prize cheque from NSERC, which isespecially welcome in a year that could, as I’ve explained previouslyin an earlier column, be a difficult one financially for the Societybecause of the unfavourable US-dollar exchange rate.But beyond the medal, certificate, and cheque, the receiptof a Michael Smith Award should remind us of something allof us already know: The RASC is a special, unique organization.We all know how special the RASC is, but isn’t it nice to haveour belief validated by the receipt of one of the premier scienceawards in Canada? We should all thank not only NSERC butalso the three individuals mentioned above who put in a greatThe Journal is a bi-monthly publication of the Royal Astronomical Society of Canada and isdevoted to the advancement of astronomy and allied sciences. It contains articles on Canadianastronomers and current activities of the RASC and its Centres, research and review papersby professional and amateur astronomers, and articles of a historical, biographical, oreducational nature of general interest to the astronomical community. All contributions arewelcome, but the editors reserve the right to edit material prior to publication. Researchpapers are reviewed prior to publication, and professional astronomers with institutionalaffiliations are asked to pay publication charges of $100 per page. Such charges are waivedfor RASC members who do not have access to professional funds as well as for solicitedarticles. Manuscripts and other submitted material may be in English or French, and shouldbe sent to the Editor-in-Chief.Editor-in-ChiefWayne A. Barkhouse136 Dupont StreetToronto ON M5R 1V2, CanadaInternet: editor@rasc.caWeb site: www.rasc.caTelephone: (416) 924-7973Fax: (416) 924-2911Associate Editor, ResearchDouglas HubeInternet: dhube@phys.ualberta.caAssociate Editor, GeneralMichael AttasInternet: attasm@aecl.caAssistant EditorsMichael AllenMartin BeechPierre BoulosRalph ChouPatrick KellyDaniel HudonEditorial AssistantSuzanne E. MoreauInternet: semore@sympatico.caProduction ManagerDavid GarnerInternet: jusloe@wightman.caContributing EditorsMartin Beech (News Notes)David ChapmanWilliam Dodd (Education Notes)Kim Hay (Society News)Bruce McCurdyHarry PulleyLeslie SageRussell Sampson (News Notes)David Turner (Reviews)ProofreadersJames EdgarMaureen OkunSuzanne MoreauDesign/ProductionBrian G. Segal, Redgull IncorporatedAdvertisingIsaac McGillisTelephone: (416) 924-7973PrintingPrint Atlantic Ltd.The Journal of The Royal Astronomical Society of Canada is published at an annual subscriptionrate of $80.00 by The Royal Astronomical Society of Canada. Membership, which includesthe publications (for personal use), is open to anyone interested in astronomy. Annual feesfor 2003, $44.00; life membership is $880. Applications for subscriptions to the Journal ormembership in the RASC, and information on how to acquire back issues of the Journal canbe obtained from:The Royal Astronomical Society of Canada136 Dupont StreetToronto ON M5R 1V2, CanadaInternet: nationaloffice@rasc.caWeb site: www.rasc.caTelephone: (416) 924-7973Fax: (416) 924-2911Canadian Publications Mail Registration No. 09818Canada Post: Send address changes to 136 Dupont St, Toronto ON M5R 1V2Canada Post Publication Agreement No. 40069313We acknowledge the financial support of the Government of Canada, through the PublicationsAssistance Program (PAP), toward our mailing costs.U.S. POSTMASTER: Send address changes to IMS of NY, PO Box 1518, Champlain NY 12919.U.S. Periodicals Registration Number 010-751.Periodicals postage paid at Champlain NY and additional mailing offices.© 2003 The Royal Astronomical Society of Canada. All rights reserved. ISSN 0035-872X254JRASC December / décembre 2003

deal of work to put forth the successfulnomination.Further details on the award will begiven in a future issue of the Journal, butI’d like to say just a bit about the MichaelSmith Awards here. According to NSERC’sofficial literature, the award “honoursindividuals and groups who make anoutstanding contribution to the promotionof science in Canada, through activitiesencouraging popular interest or developingscience abilities.” The award is named forDr. Michael Smith, a 1993 Nobel laureatewho performed revolutionary geneticresearch at the University of BritishColumbia. Equally remarkable as hisresearch was his decision to donate thehalf-million-dollar Nobel prize to otherunderfunded researchers and to scienceoutreach activities. Michael Smith, whopassed away in 2000, was a singularscientist and person, and the Society isprivileged to have won an award bearinghis name. I am sure Dr. Smith would havebeen impressed with the diverse activities— ranging from publishing world-classastronomical resources to myriad outreachand public awareness programs carriedon by 27 Centres — performed by theRASC in fulfillment of its mandate. I thinkDr. Smith would have been especiallypleased with the Society’s recent decisionto proceed with Skyways, a new publicationaimed at teachers that makes it easierfor them to deliver high-quality astronomycontent to their students at various gradelevels.In this, my final column of 2003, Ican’t help but feel a tingle up and downmy spine when I think about all the specialthings that have happened to the Societyin the past year. If our Royal Centenarycelebrations had been scripted by aHollywood screenwriter, would they havebeaten reality? Could we have asked ourscripter for anything better than aninspirational visit by the LieutenantGovernor of British Columbia at ourGeneral Assembly and recognition byCanada’s premier scientific granting agencyin the form of the granting of a prestigiousaward named for one of Canada’s mostinspirational scientists? Yes, 2003 hasbeen a very good year! Let’s give eachother heartfelt pats on the back, andcontinue all the good work into 2004 andbeyond.ADVERTISE IN THE JOURNALThe Journal accepts commercial advertising. By advertising within these pages you will reachthe over 4600 members of the RASC, who are the most active and dedicated amateur andprofessional astronomers in Canada. The Journal is also distributed by subscription to universitylibraries and professional observatories around the world.BLACK AND WHITE RATESSIZE One Insertion Three Insertions1/8 Page $125 $1151/6 Page $150 $1401/4 Page $175 $1601/2 Page $250 $225Full Page $375 $340Inside Back Cover $500 $425Outside Back Cover $750 $550For information or to receive a copy of our advertising flyer contact:RASC Journal AdvertisingPO Box 31011, Halifax NS B3K 5T9Telephone: (902) 420-5633Fax: (902) 826-7957email: ads@rasc.caDecember/ décembre 2003 JRASC255

Editorialby Michael Attas (attasm@aecl.ca)Some evenings after sunset but beforethe stars come out, I look west andsee a brilliant streak of light movingslowly through the sky. “It’s just a jet trail,”I tell myself. Since this phenomenon isnot astronomical at all, in the past I nevergave it a second thought. On one occasion,though, I recalled trying to spot Halley’sComet in 1986. After much searching Isaw a faint smear, but it was much lessimpressive than this vapour trail. So whywas I so much more excited about thecomet?Eventually I realized that the impactof what we see is very much influencedby its context; namely, what we thinkabout it. This is not a new idea, of course,but it’s very much at the heart ofobservational astronomy — okay,stargazing. Seeing the faint fuzziness ofthe Andromeda galaxy through binocularsfor the first time can be disappointing,but only if you’re expecting a photo-qualityview. It can instead be quite thrilling ifyou’re thinking about how far away thegalaxy is, how long it took the light toarrive, how huge it is, how many starsyou’re seeing at once, how many of themhave planets, how many planets mightbe inhabited, and so on. Our mindinterprets what our eyes see and sets usup to respond, either emotionally orobjectively or both.A friend once asked me if a scientificunderstanding of astronomy diminishedthe wonder of the night sky. I said no,with some hesitation, because my senseof wonder was coming and going —certainly diminished during tedioussearches for dim NGC objects duringfrosty nights! Sometimes these searcheswere hindered by auroral displays, whichbathed the sky in washes of light, drowningout the faint fuzzies. I had to pull backfrom the eyepiece and readjust my priorities.After all, the aurora was a spectaculardisplay in its own right, even though itwasn’t a deep-space phenomenon. I knowthe shimmering gray-green light comesfrom molecules of oxygen and nitrogenin the upper atmosphere, excited by highenergysubatomic particles from the sun.Does that diminish my awe at seeing thewhole sky dancing? Not a bit.It turns out that knowing what’sbehind certain phenomena usually makesthem more exciting to observe, ratherthan less exciting. You’ve probably seenbird watchers thrilled at hearing a particularcall or seeing unusual markings.Archaeology buffs also get excited aboutthings that look pretty mundane to theuninitiated. I’ve recently realized thatgeology can do the same to otherwisesane human beings, including myself.Every fall I crack open the brandnew Observer’s Handbook and study themap of meteorite impact craters of NorthAmerica, prepared by R.A.F. Grieve. Canadahas such a broad expanse of old, hardrock that impact sites are more commonthan one might imagine. They can betricky to identify, though, since the signsare often subtle. Deep, round lakes onthe Canadian Shield are suspicious,especially if they are ring-shaped or havecentral islands. West Hawk Lake, aroundthe corner from where I live, is the deepestlake in Manitoba and has been proven toCorrespondenceCorrespondanceErratum:In the August 2003 “Orbital Oddities”column (JRASC, August 2003), the authormade reference to the irrational number“Φ” which was reproduced as “M” dueto a typographical error. The secondsentence in the middle column of page182 should read:be an old crater by researchers who drilledinto its bottom. To my eyes it looks prettynormal, but I’m impressed nonetheless.Last June I decided to visit anotherclassic impact site, the Brent crater inAlgonquin Park. The Ontario road mapshowed it to be a few kilometres down adirt road off Highway 17, so after a businesstrip to Chalk River, I headed that way. It’swell marked, and in fact there is anobservation tower on the rim, a visitor’sbrochure, and a hiking trail to the bottom.Except for the hordes of mosquitoes anda few larger animals, I was alone on thetrail. The silence on the cool floor of thecrater heightened the eerie feeling in mybones while I pondered that half a billionyears ago on this very spot a stupendousexplosion had transformed the landscapein a millisecond. But if the spot had nothad a road sign, I would have driven rightby it. The traces of the impact are evidentonly to trained eyes (and minds). That’sthe point I’m trying to make: educationdoesn’t diminish our sense of astronomicalwonder; it enhances it. The more we knowabout what we are looking at, the betterwe can appreciate it. So next time you’reshowing someone the night sky throughyour telescope, take the time to explainthe view. Knowledge — it’s the naturalexperience enhancer.“Indeed, last year at this time I wasinvoking the so-called ‘most’ irrationalof all numbers (although certainly notthe most illogical),Φ, as I examined afirst-order pseudo-Fibonacci relationshipbetween Earth and Mars.”In the News Notes item “The Universeis Just A ‘Click’ Away” (JRASC, August2003) we forgot to mention that theDirector of the project is Dr. John Percyof the University of Toronto.256JRASC December / décembre 2003

News NotesEn ManchettesGEMINI SURPRISE AT EPSILON INDIWhile searching for planet-sized bodiesthat might accompany the nearby starsystem Epsilon Indi, astronomers usingthe Gemini South telescope in Chile madea related but unexpected detection. EpsilonIndi was known to host an orbitingcompanion, dubbed Epsilon Indi B, whichwas discovered last year and is the nearestknown specimen of a brown dwarf. Browndwarfs are small, low-temperature starsthirty to forty times more massive thanJupiter but of similar size. Even thoughthe Epsilon Indi system has been intensivelystudied since its brown dwarf companionwas discovered, it required the combinationof Gemini’s powerful infrared capabilitiesand the extremely sensitivespectrograph/imager called PHOENIXto reveal a third and unexpectedcompanion body. “Epsilon Indi Ba is theclosest confirmed brown dwarf to oursolar system,” says Dr. Gordon Walker(University of British Columbia), who ledthe Gemini research team. “With thedetection of Epsilon Indi Bb,” Walkercontinues, “we now know that EpsilonIndi Ba has a close companion that appearsto be another, even cooler brown dwarf.One certainty is that the Epsilon Indisystem is even more interesting than wepreviously thought.”“When the target was acquired andwe saw that there were clearly two objectsclose together, we initially thought it mustbe the wrong object. Epsilon Indi Ba,formerly called Epsilon Indi B, had beenobserved before and in those observations,no one noticed the companion object. Itwas a tremendous surprise for us,” saysDr. Kevin Volk (Gemini Observatory, LaSerena, Chile) who was actually makingthe observation at the Gemini Southtelescope along with Dr. Robert BlumFigure 1. Artistic recreation of the Epsilon Indisystem. The picture shows Epsilon Indi andits brown-dwarf binary companions. The relativesizes are not shown to scale in this illustration.Artwork by Jon Lomberg, supplied courtesyof Gemini Observatory Illustration.(CTIO, La Serena, Chile).The serendipitous nature of thedetection took the science team — whosemembers are from Canada, the U.K., theU.S., and Chile — by surprise. Dr. Blumelaborates, “We then found that thecompanion, Epsilon Indi Bb, is invisiblein the methane band where previousGemini observations had been taken. Thecoolest brown dwarfs are very faint andhard to detect, but there may be vastnumbers of them — which makes thisdetection important.”Epsilon Indi is the fifth brighteststar in the southern constellation of Indusand is located about 11.8 light years awayfrom our Solar System. The star is similarto but cooler than our Sun. The projectedseparation as seen on the sky betweenEpsilon Indi A and Indi Ba is approximately1500 AU, and the distance between EpsilonIndi Ba and the newly discovered EpsilonIndi Bb is at least 2.2 AU.The new Gemini observations showthat Epsilon Indi Bb is cooler and lessmassive than Epsilon Indi Ba, a resultthat follows from its significantly lowerbrightness and deep methane absorption.Methane absorption is a key indicatorfor low-mass objects since gaseous methanecan only exist in the lower temperatureenvironments of the atmospheres of browndwarfs and planets.Epsilon Indi Ba and Bb are membersof a recently discovered type of astronomicalobject: the so-called T class brown dwarfs.These T-dwarfs have diametersapproximately equal to Jupiter but withmore mass. Spectra of Epsilon Indi Ba,taken with PHOENIX by Dr. Verne Smith(University of Texas, El Paso) andcollaborators, show that Epsilon Indi Bahas 32 times the mass of Jupiter and a1500-degree surface temperature. It isspinning about three times faster thanJupiter. Epsilon Indi Bb has less mass, iscooler, but is still much more massiveand hotter than Jupiter. Like Jupiter, theT-dwarfs do not have enough mass tomake energy the way the Sun does fromnuclear fusion. Epsilon Indi Ba and Bbare glowing from heat resulting from themass pushing down on the interior.PHOENIX, the instrument responsiblefor producing the new data, is a nearinfrared,high-resolution spectrometerbuilt by the National Optical AstronomyObservatory (NOAO) in Tucson, Arizona,and commissioned on Gemini South in2001. Dr. Ken Hinkle (NOAO, Tucson,Arizona) comments, “PHOENIX wasdesigned for exactly this type of research.It is the first high-resolution infraredspectrograph on a Gemini telescope, andthe first high-resolution infraredspectrograph on any Southern Hemispheretelescope.”Further details and images of theEpsilon Indi system are on the Geminitelescope Web page at www.gemini.edu.SCUBA-2 A GOAn international collaboration, whichincludes astronomer Dr. René Plume ofthe Department of Physics and Astronomy,December/ décembre 2003 JRASC257

University of Calgary, has recently announcedit is moving ahead with the constructionof a new generation of astronomical camera.The camera, thousands of times morepowerful than its predecessor, is called theSubmillimetre Common User BolometerArray-2, or SCUBA-2 The project has received$12.3 million in funding from the CanadaFoundation for Innovation (CFI). Oncecomplete in 2006, SCUBA-2 will be installedon the James Clerk Maxwell Telescope (aradio telescope jointly operated by Canada,the UK, and the Netherlands) at the MaunaKea Observatory in Hawaii. With itsunprecedented sensitivity and field of view,SCUBA-2 will help researchers betterunderstand how stars and galaxies areformed. The cutting-edge technology tobe incorporated in SCUBA-2 is expectedto provide much better images than thosecurrently provided by SCUBA-1. In addition,with some 6400 detectors, SCUBA-2 willbe able to observe much larger areas of thesky than SCUBA-1, which uses only 130detectors.“To understand how stars and galaxiesare made, you need to first study the materialthat they are made from and how it isdistributed throughout the universe,” saysPlume, and “in order to do this, we needto survey the sky at radio wavelengths. Thenew technology in SCUBA-2 will give us amore detailed picture of the sky and it willalso allow researchers to complete in onenight what would normally take three yearswith SCUBA-1.”The CFI funds for the SCUBA-2 projectwas awarded to a consortium of eightCanadian universities under its InternationalAccess Fund. Researchers at the Universityof Waterloo are leading the consortium.GRB INDUCED MASS EXTINCTIONGamma Ray Bursts (GRBs) rank amongthe most energetic of explosive events thatoccur within the Universe. Produced whenmassive stars undergo gravitational collapse,GRBs literally constitute an intense burstof lethal gamma rays that propagate throughspace. Any habitable planet caught in thenear-by vicinity of a GRB-producing eventwould suffer devastating effects. Indeed,such a withering gamma-ray blast mayhave struck the Earth some 443 millionyears ago at the end of the Ordovician eraaccording to a new research report publishedin the September 24 issue of the New Scientist.Astrophysicist Dr. Adrian Melott(University of Kansas) and collaborators,including University of Calgary geologistBrian Chatterton, reached their conclusionsafter studying the trilobite extinction recordat the time of the late Ordovician. The fossildata gathered by Chatterton from theMackenzie Mountains of northwesternCanada, in particular, indicate that thosetrilobite species that lived in the planktonrich layer near the ocean surface were moreadversely affected during the Ordovicianextinction than those that dwelt in thedeeper ocean. This pattern of ocean surfacedevastation is exactly what would beexpected from a GRB interaction, Melottand co-workers argue.The key gamma-ray induced extinctionmechanisms that Melott and co-workersidentify (for both ocean-surface-dwellingtrilobites and land animals) are thedestruction of the Earth’s ozone layer andthe production of deadly toxins. As thegamma rays interact with the Earth’satmosphere a veritable “witch’s brew ofnitrogen oxides” would be produced, Melottet al. argue. In particular, the new researchreport singles out nitrogen dioxide (NO 2 )as being a particularly potent agent forblocking out substantial quantities ofsunlight and for destroying ozone. Thecombined effects of prolonged darknessand UV radiation over-exposure are theagents that devastate life on and near theEarth’s surface.It has been estimated that a GRBcapable of affecting life on Earth occursonce every five million years (or so).EARLY CHINESE ECLIPSERECORDS: A SECOND LOOKThe interpretation of ancient astronomicalrecords is, even at the best of times, adifficult and demanding task. With thisin mind, Dr. Ciyuan Liu (of the ChineseAcademy of Sciences) and co-workers,including Xueshun Liu (Ph.D. candidate,School of Asian Studies, University ofBritish Columbia), have re-evaluated aseries of two-thousand-year-oldastronomical records from the Xia, Shang,and Western Zhou Dynasties. Writing inthe June issue of The Journal ofAstronomical History and Heritage, Liuand co-workers discuss a series of supposedsolar eclipse records found in Spring andAutumn Annals as well as on oracle boneinscriptions and in passages from theBook of Songs.The researchers find that many ofthe eclipse records are, in fact, very vagueand indeed, the conclusion drawn formost of them is genuine solar eclipsesare probably not being referred to. WhatLiu et al. have deduced in a number ofcases is that the records actually indicateis that a “test” was being made. That is,the accounts do not actually say that aneclipse took place, but rather they aredivining the possible consequences shoulda solar eclipse be seen. As a result of thisnew and continuing study, Liu and coworkerscall into question the method ofdating ancient Chinese chronicles by solareclipse observability matching.Figure 2. – Fragment of a Shang dynasty oraclebone (circa 10 BC). The three characters in theupper portion of the bone fragment are ri (thesun) you (has) shi (eclipse). Liu and co-workersargue that rather than this being a record ofan actual solar eclipse, it is a divinationconcerning what would happen if a solareclipse were to be seen. Unlike the recordsrelating to lunar eclipses, Liu and co-workersargue that no clear-cut solar eclipse accountshave been found in the ancient oracle boneinscriptions. Image courtesy of Xueshun Liu.258JRASC December / décembre 2003

Johannes Kepler’s Harmonices mundi:A “Scientific” Version of the Harmonyof the Spheres, Part II 1by Bruno Gingras, McGill University (bginger@po-box.mcgill.ca)Perhaps in order to show theseriousness of his procedure, andto show that harmonic ratios arenot to be found in several relations inwhich they might have been expected tooccur, Kepler gives a summary of hissuccessive unsuccessful attempts. First,he shows that no harmonic proportionsare to be found in the periodic times ofthe planets (that is, the time required fora planet to complete its revolution aroundthe Sun). He then compares the ratios ofthe extreme distances of planets (distancesfrom the Sun at aphelion and perihelion),with harmonic intervals. This comparisonis done not only for an individual planet,but also for two adjacent planets, bycomparing their divergent extremedistances (the aphelion of the planetfarther from the Sun with the perihelionof the planet that is closer to the Sun)and their convergent extreme distances(the perihelion of the planet farther fromthe Sun with the aphelion of the planetthat is closer to the Sun). Thesecomparisons yield a few harmonicproportions, but do not give a satisfyingresult for every planet (Figure 1). Forexample, the convergent extreme distancesof Mars and Earth yield a ratio of 27/20,which corresponds to an interval betweena perfect fourth and a tritone. Furthermore,Kepler observes that harmonies are relatedto motion, therefore one should expectto find harmonic ratios in the motionsof planets and not in their relative distances.Trying to explain how musical harmoniescould be perceived through the motionof the planets, he argues “in fact, thereare no real sounds in the heavens, andthe motion is not so turbulent that awhistling is produced by friction withthe heavenly air” (Kepler 1619). In oneshort sentence, nested in the middle ofa lengthy paragraph, a tradition that stoodfor nearly two thousand years had beenswiftly debased. The celestial harmoniesmust then be perceived by another sense,and Kepler tells us that they are broughtto us through the light perceived by oureyes, which informs us of the motions ofthe planets.Accordingly, he proceeds to look atthe daily paths of the planets (that is, theactual distance traveled by a planet aroundits orbit in one day). Clearly, there are noharmonic relations to be found there(Figure 2). However, Kepler is not dauntedby this apparent failure, remarking thatthe estimation of daily paths requirecomplex calculations and thus could notbe perceived by “natural instinct.” Finally,Kepler examines the relations betweenthe apparent daily planetary motions (theapparent daily arcs created by the motionof a planet, measured in degrees) as ifthey were seen from the Sun, the ideabeing that the harmonic relations thatcould be found in these motions wouldbe conveyed in some way with the lightfrom the Sun. Since the perception ofapparent daily motions requires nocalculations, harmonic relations couldinstinctively be felt by all living creatures.The results show that musical intervals(albeit not necessarily consonant intervals)are obtained for every planet, whencomparing its apparent daily motion ataphelion and at perihelion. Moreover,when comparing the extreme convergentand divergent apparent daily motions ofpairs of adjacent planets, consonantintervals are obtained in every case (Figure3). The margin of error is very small inmost cases, being generally less than asyntonic comma (81:80), and amountingto less than a diesis (25:24) in all casesexcept for the divergent motions of Jupiterand Mars. 2 There is, however, one glaringomission in this table: the perfect fourth,one of the primary consonances, is notto be found between the extreme motionsof any individual planet, nor between theconvergent or divergent motions of anypair of planets. Fortunately for Kepler’ssystem, the relation between the extremeapparent daily motions of the Moon asseen from the Earth (that is, whencomparing the motion of the Moon atapogee and its motion at perigee) givesa perfect fourth. Although the theoreticalcoherence of the system is jeopardized1The first installment of this article appeared in the October 2003 issue of the Journal.2The syntonic comma (81:80) is the difference between a Pythagorean major third (81:64) and a just major third (5:4). The diesis (in just intonation) is thedifference between a major third (5:4) and a minor third (6:5). Note that the diesis is smaller than the semitone (16:15), calculated as the difference between aperfect fourth (4:3) and a major third.December/ décembre 2003 JRASC259

Figure 1 – Relative distances of the planets compared with harmonic intervals (from Kepler,Harmonices mundi [English translation by Aiton, Duncan & Field]).by the addition of the Moon (which isnot, properly speaking, a planet), and theuse of the Earth as a vantage point (allother daily planetary motions are perceivedfrom the Sun in Kepler’s system), one canalmost hear a sigh of relief from Keplerupon discovering this relation, as theabsence of a primary consonance suchas the fourth would have been a seriousproblem for a system that is supposed toreflect the work of the Creator.Proportions of pairs: ratios foundwhen comparing the divergent orconvergent extreme distances to the Sunof adjacent planets. The mean distancefrom the Earth to the Sun is arbitrarilyset at 1000, and all other distances areevaluated in proportion. The letters (a,b, c, etc...) refer to the quantities foundin the second column (distance ataphelion/perihelion).Proportions for the individual ones:ratios obtained when comparing theextreme distances of a single planet.Daily motions: apparent daily motionsas seen from the Sun, measured in minutesand seconds. Average distances: averagedistance from the Sun (again the distanceFigure 2 – Extreme daily motions of the planets (from Kepler, Harmonices mundi [English translationby Aiton, Duncan & Field]).from the Earth to the Sun is arbitrarilyset at 1000). Daily paths: average distancetraveled by a planet in a single day in itsorbit around the Sun (the arbitrary unitused here is the same as that used in the“average distances” column).Harmonies of pairs: harmonic ratiosfound when comparing the extremedivergent (div.) or convergent (conv.)motions of adjacent planets. The letters(a, b, c, etc.) refer to the quantities foundin the second column (apparent dailypaths). Apparent daily paths: apparentdaily motions of the planets as seen fromthe Sun, measured in minutes and seconds.Individuals’ own harmonies: ratios obtainedwhen comparing the extreme motionsof a single planet. Note that there is atypographic error in the table (which wastaken from the translation by Aiton,Duncan & Field): Mars and Mercury wereinverted. The reader should therefore read“Mars” instead of “Mercury” and viceversa.Analysis of the harmonies of pairs:a harmonic ratio of a twelfth (1:3) isobserved between the extreme divergentmotions of Saturn and Jupiter, and a ratioof an octave (1:2) is found between theirconvergent motions. A ratio of threeoctaves (1:8) is found between the divergentmotions of Jupiter and Mars, while aninterval of a double octave plus a minorthird (5:24) is found between theirconvergent motions. A ratio of a minortenth (5:12) is observed between thedivergent motions of Mars and Earth,while a ratio of a perfect fifth (2:3) is foundbetween their convergent motions. A ratioof a major sixth (3:5) is observed betweenthe divergent motions of Earth and Venus,while a ratio of a minor sixth (5:8) is foundbetween their convergent motions. Finally,a interval of a double octave (1:4) isobserved between the divergent motionsof Venus and Mercury, while a ratio of amajor sixth (3:5) is found between theirconvergent motions.Kepler remarks that an importantdistinction should be made betweenharmonies set out between the extrememotions of a single planet, and those thatare found between combinations of planets,“because the same planet when it issituated at its aphelion cannot at the260JRASC December / décembre 2003

seventh degree of this scale is usually Fnatural, F# was frequently used, and thisis mentioned by Kepler as a justificationfor including the motion of Mars ataphelion. C sharp, representing the motionof Mercury at aphelion, is also included,as Kepler indicates all apparent motionsthat fit notes within a comma, even ifthey are not part of the scale. All theextreme motions of the six known planetsare thus represented, except for theperihelion motions of Earth and Venus.Figure 3 – Apparent daily motions of planets (from Kepler, Harmonices mundi [English translationby Aiton, Duncan & Field]).same time also be at its perihelion, whichis opposite, but of two planets one canbe at its aphelion and the other at itsperihelion at the same moment of time.Thus the proportion of simple melody ormonody, which we call choral music andwhich was the only kind known to theancients, to the melody of several voices,called figured and the invention of recentcenturies, 3 is the same as the proportionof the harmonies which are indicated byindividual planets to the harmonies whichthey indicate in combination” (Kepler1619). In other words, not only doesKepler’s theory of celestial harmony takeinto account the most recent developmentsin astronomy, such as the heliocentricityof the solar system and the eccentricityof the planetary orbits, but it alsoincorporates what he believed to be recentdevelopments in music, such as polyphonyand counterpoint.In Chapter V Kepler proceeds toshow how musical scales can be assembledout of the relations between the planetarymotions that were presented. Assumingoctave equivalence, he divides the apparentdaily motions of the planets by two untilall the motions can be comprised withinan octave (or within a factor of two, toput it another way). The motion of Saturnat aphelion, which is the slowest apparentmotion of all planets, is taken to be thelowest note of the system, which is G. Adurus scale (which corresponds more orless to our major mode) 4 is then built byassociating apparent motions of otherplanets to notes of the scale in such away that the relation between the apparentmotions corresponds to the musicalinterval between notes of the scale (Figure4). All the notes of the durus scale beginningon G (within a single octave) are obtainedexcept for A. Kepler justifies the fact thatA is left out by pointing out that it wasnot represented either by the harmonicdivisions that were carried out in BookIII in order to build the durus scale.Undoubtedly, this correspondence betweenthe musical theorems presented in BookIII and the actual scale created by theapparent motions of the planets musthave been seen by Kepler as an eloquentconfirmation of his theory. Although theFigure 4. Construction of the durus (top) andmollis (bottom) planetary scales (from Kepler,Harmonices mundi [English translation byAiton, Duncan & Field]).As for the mollis scale (Figure 4),corresponding to our minor mode, theperihelion motion of Saturn is taken asthe lowest note this time. F is left out(again, Kepler justifies this by saying thatit was not represented by the harmonicdivisions used to construct the mollisscale in Book III). All planetary motionsare represented except Saturn at aphelion,Mars at perihelion, and Venus at aphelion.For Kepler, the fact that the two maintypes of musical scales used by musiciansof his time are found in the heaven indicatesthat musicians are merely “aping God theCreator, and as it were acting out aparticular scenario for the ordering of3 Kepler believed polyphony to be a recent invention.4Walker (1978) notes that in Book III, Kepler “describes the two genera, molle and durum, in such a way that they seem to be the same as our minor and majormodes.” Although this seems to work with scales, it does not seem to be the case with chords (see footnote 6).December/ décembre 2003 JRASC261

the heavenly motions” (Kepler 1619).So far, only the extreme apparentdaily motions of the planets have beenconsidered. However, by including all theintermediary motions (that is, the apparentmotions observed when a planet movesfrom its perihelion to its aphelion aroundthe course of its orbit), one would obtaina particular range, or tessitura, for eachplanet. 5 This is shown by Kepler in ChapterVI, where he assigns a particular modeto each of the planets, remarking that,although his musical representations ofthese intermediary motions seem toindicate an discrete intervallic motion,the pitch would in fact be continuallychanging, in a way likened by Walker(1978) to the “wailing of a siren.” Thelowest note for each planet is taken fromthe durus scale previously constructed,except in the case of Jupiter and Mercury,for which the lowest note is that assignedin the mollis scale (Figure 5). Saturn,which covers a major third from G to B,is assigned the Mixolydian orHypomixolydian mode, while Jupiter,going from G to Bb, is associated withthe Dorian or Hypodorian mode. Sincethe range of Mars covers a fifth, and giventhat the aphelial note of Mars is close toF in the durus scale (in fact, it is F#), itwould indicate the Lydian or Hypolydianmode. The difference between the extrememotions of Earth is only a semitone, soKepler assigns it to the Phrygian orHypophrygian mode, which is the onlymode beginning with a semitone. Heremarks, in a marginal pun, that “theEarth sings ‘mi-fa-mi’, so that even fromthe syllables you may guess that in thishome of ours misery and famine holdsway” (Kepler 1619). Venus stays on asingle note, but because this note is E inthe durus scale, Kepler also associatesVenus to the Phrygian-Hypophrygianmodes. Finally, Mercury, covering a minortenth, is suited to all the modes.In Chapter VII Kepler, who clearlysees the development of polyphony andcounterpoint as an impressive achievementof “modern” music, expresses the wishthat a contemporary composer will attemptto write an “ingenious motet” that willreflect the harmonies of the planets. Heproceeds to construct in a systematicfashion all the “universal harmonies” thatFigure 5 – The “vocal ranges” of the planets (from Kepler, Harmonices mundi [English translationby Aiton, Duncan & Field]).could be created, by having the combinationof the apparent motions of all six planetsstand in harmonic relation at a giventime. Because of the very slow motion ofouter planets such as Saturn, which takes30 years to complete its revolution aroundthe Sun, and considering the limited“vocal range” of some planets, Kepleracknowledges that six-part celestialharmony will occur very infrequently.Indeed, he remarks that “harmonies offour planets begin to spread out over thecenturies, and those of five planets overmyriads of years,” and actually doubtswhether a six-part harmony among theplanets could occur more than once overthe course of history. He suspects that,if one could calculate a past moment ofuniversal harmony, it would be the exactmoment of Creation.Because of the limited tessitura ofVenus and the Earth, these two planetscannot make more than two consonancesbetween themselves: a major sixth (Earthat aphelion and Venus at perihelion), anda minor sixth (Venus at aphelion andEarth at perihelion). Two “hard” chords,in which there is a major sixth betweenthe notes sung by the Earth and Venus,involving all six planets can be obtained:the first chord is an E minor chord in firstinversion, and the second a C major chordin 6/4 position (Figure 6). 6 Two “soft”chords, in which one finds a minor sixthbetween the Earth’s note and Venus’ note,can be obtained, one being a E flat major6/3 chord, and the other a C minor 6/4chord (Figure 12). 7 Since Venus can only“sing” E (in the durum scale), or Eb (inthe mollis scale) it is the most limitingplanet, and Kepler therefore discussespossible five-note harmonies excludingVenus, and four-note chords, excluding5Although Kepler does not explicitly say so, it should be understood that, the eccentricity for the orbit of each planet being different, the “musical range” ofeach planet would be different (for a planet whose orbit is very eccentric, such as Mercury, the difference between the apparent motions at aphelion andperihelion would be much greater than for a planet whose orbit is only slightly eccentric, such as the Earth or Venus).6Here, “hard” or durus apparently refers to chords using B natural, while “soft” or mollis refers to chords using B flat. Hence, Kepler’s classification of chordsinto “hard” and “soft” has nothing to do with their major or minor quality. To indicate the distinction between Kepler’s use of the terms durus and mollis forscales and for chords, we chose to use the English equivalents “hard” and “soft” when discussing harmonies.7According to Aiton, Duncan & Field, Kepler was aware that the 6/4 chord was treated as a dissonance by most composers, but accepted it on the groundsthat the fourth had been geometrically demonstrated to be a consonance in Book III of Harmonices mundi.262JRASC December / décembre 2003

Figure 6 – Universal harmonies of the “hard” kind (from Kepler, Harmonices mundi [Englishtranslation by Aiton, Duncan, & Field]).Venus and the Earth (whose range, beingonly a semitone, is also a limiting factor).Kepler uses an idiosyncratic notationin which the musical lines added abovethe bottom staff, although grouped byfive, must still be read in the bass clef.Moreover, the octaves are indicated byusing lowercase Roman numerals (i, ii,iii, etc.). Note that Kepler does not assumeoctave equivalence when building universalharmonies. Since the apparent dailymotions of planets closer to the Sun aregreater, these planets will “sing” in a higherregister; hence, Mercury has the highestregister, while Saturn has the lowest.Since Kepler uses all the intermediaryapparent motions of the planets to buildthese chords, certain planets, such asMercury, can “sing” several notes thatbelong to the chord. Kepler also indicatesthe lowest and highest “tunings” possiblefor a given chord; these tunings indicatethe range of apparent motions possiblefor a given planet within a single harmony.The first chord is an E minor 6/3chord, while the second chord is a C major6/4 chord. In the first chord, Saturn andMars can “sing” G (g in the case of Mars)or h, while Mercury can take G, h, or e atsome point in its orbit. The remainingplanets, Jupiter, Earth, and Venus, aremuch more restricted, and can take onlyone note (h for Jupiter, g for the Earth,and e for Venus). In the second chord,Saturn can take G, Jupiter c, Mars c andg, the Earth g, Venus e, and Mercury cantake all three notes.See Figure 6 for an explanation ofthe musical notation, the register of theplanets, and the “tunings.” The first chordis an E flat major 6/3 chord, while thesecond chord is a C major 6/4 chord. Inthe first chord, Saturn and Mars can “sing”G (g in the case of Mars) or b (b standsfor B flat), while Mercury can take G, b,or d e (d e stands for E flat) at some pointin its orbit. The remaining planets, Jupiter,Earth, and Venus can take only one note(b for Jupiter, g for the Earth, and d e forVenus). In the second chord, Saturn cantake G, Jupiter c, Mars g, the Earth g,Venus d e , and Mercury can take all threenotes (it actually can “sing” five differentnotes in this chord, given its wide tessitura).Chapter VIII briefly describes thevocal attributes of each planet: althoughhe reminds the reader that planetarymotions are soundless, Kepler noticesanalogies between the roles of the planetsand those of singers in a choir. Jupiterand Saturn cover harmonic intervals andhave a distance between them varyingfrom an octave to a twelfth, just as a basspart that makes harmonic leaps, Mars“is free, but proceeds modestly,” in analogyto a tenor part, while the narrow rangeof Earth and Venus is, according to Kepler,typical of an alto part. Finally, Mercury,which is the planet that moves the fastestand has the largest range, is likened to asoprano.In Kepler’s view, every particularityof the solar system has to be explainable,since God would not have created theworld using random or arbitraryproportions. Hence, the fact that theeccentricity of planetary orbits variesfrom planet to planet (an element thatcould not be explained by his planetarylaws) is seen as necessary in order thatharmonies of all kinds be established.Chapter IX constitutes an extremelysophisticated attempt to prove that, sincethe harmonies between the motions ofthe planets are perceived by comparingthe extremes of their motions (apparentmotions at perihelion and aphelion), Godcreated the solar system so that theeccentricities of the orbits of each planetwould be built according to those relations.December/ décembre 2003 JRASC263

Figure 7 – Universal harmonies of the “soft” kind (from Kepler, Harmonices mundi [Englishtranslation by Aiton, Duncan & Field]).A lengthy set of propositions, axioms,and theorems, which will not be discussedhere on account of its complexity, is listedin order to justify this proposition.Kepler concludes his book with aphilosophical epilogue in which heentertains the possibility that the Sun,being the centre of the solar system,and the place from which the harmonyof the world radiates, would in fact bethe seat of the government of nature,populated with princes and chancellors,and perhaps even spiritual beings(although Kepler is careful about notstating anything that would be contraryto Catholic faith). He also presents hisdreamy vision of other planets and theirinhabitants, concluding with a prayerto God, who shall be praised by theheavenly bodies, by the celestialharmonies and all those who can perceivethem, and finally by his own soul.Although the Mysteriumcosmographicum was warmly receivedin 1596 and even enjoyed a reprint in1621, and in spite of the fact that Keplerwas widely recognized as a brilliantastronomer and mathematician, theHarmonices mundi seems to have hadlittle influence on his contemporaries.Besides the fact that it was understoodby very few readers given its complexarray of metaphysical speculation, its useof advanced mathematical and geometricaltools, and obviously its reliance on thelatest developments in astronomy, thetreatise was written at a time in whichtheoretical speculation was quickly beingsuperseded by experimental science,championed by Kepler’s occasionalcorrespondent, Galileo. Moreover, althoughthe belief in a God-created world wasprevalent in the 17th century, an increasingnumber of scientists and philosophersdoubted that the structure of the worldshould reflect archetypes, whetherPythagorean ratios, Platonic solids, orharmonic relations.Among the few contemporaries whodiscussed Kepler’s theory of celestialharmonies, the opinions are very diverse.The English astronomer Jeremiah Horrocks(1618–1641), an ardent proponent ofKepler’s physical and harmonic theories,wrote an Astronomia Kepleriana defensa& promota, published posthumously in1673 (Stephenson 1994). Horrocks, praisingKepler for his pioneering work in the fieldof celestial harmonies, remarked that hisHarmonices mundi went well beyond thespeculative writings of the musicamundana tradition. One can supposethat, had Horrocks not died at such ayoung age, he might very well have pursuedKepler’s ideas further. The Jesuit GiovanniRiccioli (1598–1671), whose unfinishedAlmagestum Novum (an encyclopaedicanthology of astronomical theories)includes a summary of Kepler’s Harmonicesmundi, agreed that celestial harmoniesshould be sought in the motions of theplanets and not in the relative distances,but questioned the very idea of musicamundana, wondering why harmonicproportions should be intrinsic to theheavens and remarking that this traditionshould be understood as a poeticalmetaphor. Another Jesuit, AthanasiusKircher, criticized Kepler’s margin of errorin his Musurgia universalis (1650), arguingthat Kepler was playing a game that hewas bound to win. However, as Walker(1978) points out, one can suppose thatKepler was very critical about his ownwork, having tried various solutions fortwenty years before he found one thatsatisfied him.Meanwhile, other cosmogonies weredeveloped by contemporary writers, suchas the aforementioned Kircher and RobertFludd (Utriusque cosmi majoris scilicetet minoris metaphysica, physica atquetechnica historia, published in 1617–1621).In contrast to Kepler, whose theoriesrelied heavily on observation and physicallaws, Kircher and Fludd emphasized occultdoctrines such as the macrocosmmicrocosmcorrespondence, and did not264JRASC December / décembre 2003

ely on empirical laws (Gouk 2002).However, although Kepler, who criticizedFludd’s theories, clearly believed that histheory of celestial harmony was definitive(he hoped that if it was to be ignored byhis contemporaries, it would certainlybe appreciated by readers in a fewcenturies), he nevertheless attempted toexplain the structure of the world in termsof concepts, such as universal harmoniesand geometrical archetypes, that we woulddefine today as “occult” or “metaphorical.”A few decades later, Newton’s astronomicaltheory was entirely based on mathematicsand physics, while the growing scienceof acoustics had superseded the age-oldtradition of the harmony of the spheres.As for the physical significance ofKepler’s celestial harmonies, althoughhis observations are still considered validand quite accurate by today’s astronomers,the validity of his cosmological theoryhas been shattered by the discovery ofUranus in 1781, and later of Neptune andPluto, since the relative distances to theSun and the apparent motions of theseplanets cannot be accounted for by histheory. So far, modern science has notbeen able to provide an satisfyingexplanation for the harmonic ratios foundbetween the six “ancient planets,” and,in retrospect, one might be tempted tosay that Kepler built a monumental theoryto account for, and explain, what seemstoday to be merely an intriguingcoincidence.ReferencesChailley, J., & Viret, J. 1988, L’Harmoniedes Sphères, in La Revue Musicale,408, 75Field, J.V. 1988, Kepler’s GeometricalCosmology (Athlone Press: London)Godwin, J. 1987, Harmonies of Heavenand Earth (Inner TraditionsInternational: Rochester)Gouk, P. 2002, The Role of Harmonics inthe Scientific Revolution, in TheCambridge History of Western MusicTheory, ed. T. Christensen (CambridgeUniversity Press: Cambridge), 223Kepler, J. 1619, Harmonices mundi [TheHarmony of the World], translatedinto English with an introductionand notes by Aiton, E.J., Duncan,A.M. & Field, J.V. 1997 (AmericanPhilosophical Society: Philadelphia)Martens, R. 2000, Kepler’s Philosophyand the New Astronomy (PrincetonUniversity Press: Princeton)Murchie, G. 1961, The Music of the Spheres(Riverside Press: Cambridge,Massachusetts)Stephenson, B. 1994, The Music of theHeavens (Princeton University Press:Princeton)Walker, D.P. 1978, Studies in MusicalScience in the Late Renaissance(Warburg Institute: London)Bruno Gingras is a Ph.D. candidate in musictheory at McGill University, Montreal. He isinterested in counterpoint and musicperception/cognition, and more generally inways to combine his interest in music withhis interest in science.ARE YOU MOVING? IS YOUR ADDRESS INCORRECT?If you are planning to move, or your address is incorrect on the label ofyour Journal, please contact the National Office immediately:(888) 924-7272 (in Canada)(416) 924-7973 (outside Canada)email: nationaloffice@rasc.caBy changing your address in advance, you will continue to receive allissues of the Journal and SkyNews.December/ décembre 2003 JRASC265

ReflectionsNewtonian Opticksby David M.F. Chapman, Halifax Centre (dave.chapman@ns.sympatico.ca)Figure 1 – A postcard depicting one of fourstamps issued by the Royal Mail in 1987 tocommemorate the 300th anniversary of thepublication of Newton’s Principia.“Nature, and Nature’s Laws lay hidin Night:God said, Let Newton be! and Allwas Light.”— Alexander PopeThe coming year marks the 300thanniversary of the publication ofIsaac Newton’s Opticks, subtitleda treatise on the reflexions, refractions,inflexions, and colours of light. This isone of two significant publications byNewton, the other being Philosophiaenaturalis principia mathematica (oftenshortened to Principia), which laid outNewton’s laws of motion and the theoryof universal gravitation. Although Newtonpublished the Principia in 1687 and Opticksin 1704, the concepts in these two majorworks originated in Newton’s “miraculousyear” in 1665-66, when he was only 22years old, playing hooky from TrinityCollege, Cambridge, and avoiding theGreat Plague.I will not go into a detailed biographyof Newton here (there is too much to tell!).Newton was born on Christmas Day, 1642,(Julian calendar) in Woolsthorpe Manor,Lincolnshire. His father had died onlymonths before, and Isaac was raised byhis grandmother after age 3, when hismother remarried and moved away. Hisgreat intellect lay dormant until his midteens.He entered Trinity College as anundergraduate in 1661 and remainedthere for 40 years, resigning in 1701 theprofessorship he had held for over 30years. In the latter part of his life, heturned to politics, sitting as Member ofParliament for Cambridge University andaccepting an appointment as Master ofthe Royal Mint. He was President of theRoyal Society from 1703 until his deathin 1727 at the age of 84. He was knightedin 1705, not for his scientific achievementsbut for his service to the Crown. He hadgood health all his life and never married.Isaac Newton is buried in WestminsterAbbey, London.The two books, Principia and Opticks,make an interesting comparison: Principia(1687) is the longer of the two, by far, andwas written entirely in Latin, as was thecustom for scientific works of the day.Opticks (1704) was written in English, asscientists had begun to write in theirnative languages by that time; however,it was translated into Latin for export!Principia was the culmination of all ofNewton’s ideas on dynamics and gravitation,and it would not have seen the light ofday without the financial assistance andmoral support of Edmond Halley (1656-1742), clerk and editor of the Royal Society.Newton, for his great intellect, was verysensitive to criticism, and several timesin his career threatened to stop publishinghis findings, in reaction to the harshcritiques of other scientists. Principia isa triumph of physical theory andmathematics, and turned the somewhatobscure Newton into a celebrity. After itspublication, however, his interest inmathematics waned.Opticks, on the other hand, has hardlya shred of mathematics in it (if you don’tcount geometry!). It is very much anaccount of Newton’s own experimentswith light, and all his conclusions arecarefully established through directobservation. Newton’s very first words inOpticks (after the Preface) are:“My design in this book is not toexplain the properties of light byhypotheses, but to propose andprove them by reason andexperiments.”His closing remarks in Opticks echo thistheme, and suggest that he regardsexperiment to be superior to theory:“...the investigation of difficultthings by the method of analysisought ever to precede the methodof composition. This analysisconsists of making experimentsand observations, and in drawinggeneral conclusions from them byinduction, and admitting noobjections against the conclusionsbut such as are taken fromexperiments, or other certaintruths.”266JRASC December / décembre 2003

These mildly defensive remarks stemfrom the reaction he received years earlier,in 1669-76, when he presented his initialfindings on light and colour to the RoyalSociety. Because Newton “believed” inthe corpuscular nature of light, he wasridiculed by Robert Hooke (1635-1703),curator of the Royal Society, and Dutchphysicist Christiaan Huygens (1629-95),who both favoured a wave theory of light.He was astonished at their rejection ofthe evidence he had carefully assembledin support of his findings. There are severalironies in this story: although Newtonbelieved that light had a particle nature,this belief did not play a large role in hisdeductions of the properties of light fromexperiment. On the other hand, his criticshad developed only a primitive versionof wave theory, and could explain veryfew phenomena. For instance, theconnection between wavelength andcolour was not known, and thesuperposition (i.e. interference) of waveswas not understood. The world had towait until the following century for animproved wave theory of light, developedby Thomas Young (1773-1829) andAugustin Fresnel (1788-1827), amongothers (but that is another story). In themeantime, Newton allowed for a certain“waviness” in his light rays, in his attemptto explain coloured interference fringesand what were evidently diffraction effectsin his experiments. Newton had the lastlaugh, in a sense: in the early 20th century,Albert Einstein (1879-1955) was awardedthe Nobel Prize in part for his work onthe photoelectric effect in metals, in whichhe was compelled to conclude that lightinteracted with matter as a particle! Infact, the current model of light has a dualnature, neither exclusively a wave norexclusively a particle (spanning theelectromagnetic spectrum, one neverhears scientists speak of “radio rays” or“gamma waves”). I like to think of lightas travelling and diffracting as a wavebut interacting and exchanging energyas a particle.A large part of Opticks is devotedto an examination of the dispersion oflight passing between two media of differentrefractive indices, or “refrangibility” asNewton would say. Working with prisms,lenses, and a ray of sunlight passingthrough a small hole in a window blind,Newton performed a series of experimentsshowing that blue light was “bent” morethan yellow, yellow more than red, andso on. He also proved that white light wasmade up of all the colours. He convincedhimself that refracting telescopes, withtheir dispersive objective lenses, wereinherently faulty, and would always sufferfrom chromatic aberration, focussinglight of different colours at different focallengths, thus creating composite imageswith multi-hued coronas. Accordingly,Newton followed up on the suggestionby the Scottish mathematician JamesGregory (1638-75) that a telescope witha curved objective mirror would directall light to the same focus, irrespectiveof colour. Newton made several telescopesbased on this principle, using metallicmirrors, and presented one to the RoyalSociety in 1671, after which he was electeda Fellow. His description of mirror-grindingmay be of interest to modern telescopemakers!(I did not see any account ofNewton using his telescope forastronomical purposes, but I did not lookthat hard.)There is an epilogue to the chromaticaberration story: Newton was wrong! Hisfriend David Gregory (1659-1708), professorof astronomy at Oxford and nephew toJames Gregory, noticed that glass prismsof different composition refract the samecolour of light to different degrees. Hereasoned that a compound refractingobjective made with lenses of two differenttypes of glass could be made virtually freeof chromatic aberration. Optician JohnDolland (1706-61) constructed such a lensin 1758, and was widely recognized for theachievement (in 1729, the London barristerChester Hall (1703-71) had devised a similarlens, but did not purse it commercially).Such achromatic lenses and their variantsare used in all good quality modern refractors,but Newton’s reflecting telescope (and itsvariants) remains king of the large-aperturetelescopes.Perhaps the crowning achievementof Opticks is Newton’s explanation of thecolours of the rainbow. The fundamentalray theory of the bow, explaining thegeometry and angles, had been developedearlier by René Descartes (1596-1650)and others. Applying his new-foundunderstanding of dispersion of light,Newton was able to explain how differentpure colours of white light are dispersedand deviated into overlapping angularbands. In this way, he explained the orderof the colours of the primary bow andthe reverse order of the colours of thesecondary bow. He also explained theunder-appreciated fact that the coloursof the rainbow are not pure (due to theoverlapping bands) as are the coloursderived from a prism. In other words,there is no unique mapping of wavelengthto angle in the rainbow.All in all, astronomers have a lot tothank Newton for. I find it astonishingthat so much insight could emerge froma 22-year-old brain in such a short time,even if it did take nearly a lifetime todocument. As a mark of respect for thisgreat intellect, each one of us should findtime to crack open a copy of Opticks inthe coming year, its 300th anniversary.There is a Dover Books edition; Volume34 of Encyclopedia Britannica’s GreatBooks of the Western World contains it(and the Principia); and it is availableonline as a pdf file at dibinst.mit.edu/BURNDY/Collections/Babson/OnlineNewton/Opticks.htm.“The marble index of a mind foreverVoyaging through the strong seasof thought, alone.”— William Wordsworth,contemplating Newton’s bustDavid (Dave XVII) Chapman is a Life Memberof the RASC and a past President of the HalifaxCentre. This is his 40th article since he startedwriting Reflections in 1997. By day, he is aDefence Scientist at Defence R&D Canada-Atlantic. Visit his astronomy page atwww3.ns.sympatico.ca/dave.chapman/astronomy_page.December/ décembre 2003 JRASC267

Second LightAsteroid Spins are Solar Poweredby Leslie J. Sage (l.sage@naturedc.com)We all experience daily the effectsof the second law ofthermodynamics, which looselystated declares that the amount of disorderin any system will increase over time(unless external work is done). This isparticularly obvious in the bedrooms ofour children, but the same principle appliesthroughout the Universe. Within our SolarSystem, asteroids bang into each other.Not frequently, but often enough thatover time their spins should be prettyrandomly distributed. About a year ago,however, Steve Slivan of the MassachusettsInstitute of Technology reported that afamily of asteroids — a group arisingfrom the destruction of a larger bodyduring a collision — had several clustersof spin orientations and speeds (seeSeptember 5, 2002 issue of Nature), ratherthan a random distribution. This wasunexpected, though Richard Binzel (alsoof MIT and Slivan’s Ph.D. advisor) hadseen hints of it 15 years ago. Slivan hadno explanation for his result. Now DavidVokrouhlický of Charles University in theCzech Republic and his collaborators atthe Southwest Research Institute inBoulder, Colorado have found that thosepeculiar asteroid spins result from theeffects of sunlight (see September 11,2003 issue of Nature).The asteroids with the peculiar spinsare in the Koronis family (in the mainasteroid belt), which resulted from acatastrophic collision several billion yearsago. The asteroid family members haveorbits that are quite close to each other,and therefore they should have collidedwith each other and many more“background” asteroids since the familywas formed. The asteroids with progradespins (counterclockwise as seen fromabove the plane of the Solar System, andthe direction of orbital motion of all theplanets) have nearly identical “days,” withspin periods of 7.5-9.5 hours. They alsohave similar obliquities (inclination ofthe spin plane with respect to the planeof the Solar System) of 42-50 degrees. Theasteroids with retrograde spins all haveobliquities between 154 and 169 degrees,and periods of either less than 5 hoursor greater than 13 hours. This is a verynon-random distribution and was aboutas expected as a bunch of marblesspontaneously rearranging themselvesinto a nice square over time.David Vokrouhlický, along with hiscollaborators David Nesvorný and BillBottke, have now figured out why theasteroids have the spins they do. In additionto explaining this puzzling result, theirwork has wide-ranging implications forour understanding of all asteroids.The explanation lies in the waysunlight is reflected from and re-emitted(in the infrared) by irregularly shapedasteroids. The sunlight acts like wind ona windmill, producing a torque. Part ofit comes from the difference betweenmorning and afternoon temperatures.We’re all familiar with the fact that daytimetemperatures on the Earth are notdistributed symmetrically around localnoon. Rather, it is hotter three hours afternoon than it is three hours before noon.This means that the afternoon side of aplanetary body emits more thermal(infrared) radiation than the morningside, and there will be a slight recoilbecause of this asymmetry. A Russianengineer named Yarkovsky wrote aboutthe effect on planets in the early part ofthe 20th century, and the application toasteroids was first determined aroundthe beginning of the 21st century. The“YORP” effect (for Yarkovsky-O’Keefe-Radzievskii-Paddick) includes the Yarkovskyeffect, in addition to the direct effect ofthe sunlight hitting the asteroid.A model applying the YORP effect,as well as solar gravitational torques andplanetary gravitational perturbations,was constructed by Vokrouhlický et al.,who let the Koronis asteroid family evolvenumerically for several billion years. Whatthey found was that asteroids in the sizerange of 20-40 km that had prograde spinsslowed down and their obliquities twisteduntil they were in a resonance with changesin Saturn’s orbit. Vokrouhlicky has namedthese “Slivan states,” after the discoverer.The obliquities and spin periods comingfrom the model matched what is seen inthe real Koronis family. The retrogradespinningasteroids aren’t affected byplanetary resonances, so the torque arisingfrom the thermal effects first have theirobliquities driven till they are almost“upside down,” and then they are eitherspun up or spun down, as observed. Thesmaller the asteroid, the more quickly itis driven towards one of these spin states.The model results are such a goodmatch for the observational data that itis hard to imagine that this isn’t the rightexplanation.Beyond explaining Slivan’s results,Bottke thinks that the YORP effect maywell explain some other anomalousobservations. There are many asteroidswith diameters less than 40 km that haveeither very fast or very slow rotation rates,which may have been driven by sunlight.Some asteroids may have been spun upso much that they start ejecting mass,especially if they are “rubble piles” —asteroids that are loosely held together268JRASC December / décembre 2003

only by gravity, rather than being solidrock. Such shedding might even give riseto asteroidal moons, which appear to bemore common than expected. In particular,Vokrouhlicky suggests that the satelliteDactyl of the asteroid 243 Ida may havearisen this way.This is not to say that collisionsbetween asteroids don’t have any effect.But it may well be that collisions generallyare an inefficient means of transferringangular momentum to the target asteroid.It looks like solar power isn’t just forcalculators anymore — now it movesaround mountain-sized asteroids!Dr. Leslie J. Sage is Senior Editor, PhysicalSciences, for Nature Magazine and a ResearchAssociate in the Astronomy Department atthe University of Maryland. He grew up inBurlington, Ontario, where even the brightlights of Toronto did not dim his enthusiasmfor astronomy. Currently he studies moleculargas and star formation in galaxies, particularlyinteracting ones.Amateur astronomers could fairly easily be involved in observations similar to those done by Slivan. He used a 61-cm telescopewith a 384 × 576 pixel CCD and a V-band filter. The key is to take relatively short exposures (Slivan used 5-min unguidedexposures, simply tracking at the sidereal rate), because you get the spin rates from periodic variations in the light curves ofthe asteroids. Differential photometry from stars in the same image gives you the relative brightness changes from exposure toexposure — this must be done very carefully in order to achieve the kinds of results necessary to be useful to professionals. Youdon’t need particularly good seeing to do this, though of course everything is faster and easier with good seeing. But Slivan’sdata were taken in suburban Massachusetts, where he had to use a stellar “size” of about 12 arcseconds when reducing his data.For more information, see the Web site www.koronisfamily.com.ANOTHER SIDE OF RELATIVITYi can’t decide if i shouldcall it theski-dobor thedob-sleigh!what doyou think?how aboutthe dope-scope?©2004December/ décembre 2003 JRASC269

FROM THE PASTAU FIL DES ANSFALLING STARSBright falling stars I greet you with a smile,For you beguile,My loneliness, with pleasure pure and sweetIn moment’s fleet.In coloured beauty and in lustre dressed,Never at rest,You span the sky and gild the heav’nly wayWith sparkling ray.I only know the moments of your birth,Above the earth;As she performs her yearly round in spaceYou run your raceAnd pierce the blue just as a flashing bladeTo quickly fade.Along your flight the burning embers sowAn after-glow,To mark your path amid the stars of night,With guiding light.I never know the instant when you willDisturb the stillOf Heaven’s stars and speed athwart the skyAll silently.Nor can I tell in Nature’s open book,Just where to look,To watch your coruscations wax and fadeAmid night’s shade.Adown the east or west your fiery ballMay headlong fall,Or, slowly, stream along the starry heightIn graceful flight.Whene’er you come you bring a joyous thrillMy soul to fill.Oh messsengers from distant worlds! I yearnYour tale to learn,And I await, amid earth’s frosted dews,Celestial news.by W.F. Denning,from Journal, Vol. 9, p. 60, February, 1915.270JRASC December / décembre 2003

Research PapersArticles de rechercheTHE JANUARY 26, 2001 FIREBALL AND IMPLICATIONSFOR METEOR VIDEO CAMERA NETWORKSBY Martin ConnorsAthabasca UniversityElectronic Mail: martinc@athabascau.caPeter BrownUniversity of Western OntarioElectronic Mail: pbrown@uwo.caDouglas P. HubeUniversity of AlbertaElectronic Mail: dhube@Phys.UAlberta.CABrian MartinThe King’s University CollegeElectronic Mail: brian.martin@kingsu.caAlister LingEdmonton CentreDonald HladiukCalgary CentreElectronic Mail: Don_Hladiuk@hotmail.comMike MazurUniversity of Calgaryand Richard SpaldingSandia LaboratoriesElectronic Mail: respald@sandia.gov(Received January 21, 2003; revised August 6, 2003)Abstract. A bright fireball was observed from central and southern Alberta in the early evening of January 25, 2001 (January 26 UT).The event was recorded with three all-sky video cameras in and near Edmonton, on one video camera located in Calgary, and by manyvisual observers. Visual and taped observations indicate an agreement of a duration of 2 to 4 1/2 seconds. There were several reports ofsonic booms. The peak brightness was comparable to the Full Moon. Analysis of all available data indicates that a meteorite fell near BigValley, Alberta, although several field searches failed to recover any fragments. Improvements to equipment and methods of analysis willimprove the chance of recovering meteorites in future using all-sky cameras and refined astrometric measurement techniques.Résumé. Un bolide brilliant a été observé le soir du 25 janvier 2001 (26 janvier, temps universel) du centre et du sud de l’Alberta.L’événement a été enregistré par trois appareils vidéo captant tout le ciel visible des environs d’Edmonton, par un appareil à Calgary,ainsi que par maints observateurs visuels. Ces observations ont indiqué que l’événement a duré de 2 à 4,5 secondes. Des éclats soniquesont été entendu et l’intensité lumineuse se rapprochait de celle de la pleine lune. Une analyse de toutes les données recueuillies indiquequ’un météorite est tombé près de Big Valley, Alberta, quoique des recherches dans les champs environnants n’ont réussi à récupéreraucun fragment. Des améliorations de l’équipement et des méthodes d’analyse devront à l’avenir améliorer la probabilité de récupérerdes météorites, en se servant de caméras ‘tout ciel’ et de techniques de mesure de données astrométriques.December/ décembre 2003 Journal of the Royal Astronomical Society of Canada, 97: 271 – 276, 2003 December 271

1. IntroductionThe value of meteorites as sources of information about the formationand early evolution of the Solar System is well recognized (Wasson1985). The value of a meteorite is greatly enhanced if its solar orbitis known and, hence, if its original dynamical relationship with otherSolar System objects can be established.Several meteor camera networks have been operated in Canada,Europe, and the United States (Halliday et al. 1978). Observation ofa meteor event from two or more sites, along with angular velocityinformation, permits determination of a fall zone for any survivingfragments. This information also allows determination of the trajectoryin space prior to entering Earth’s atmosphere, and with appropriatecorrections, the original orbit. In addition, it has been possible toestimate the initial mass and derive limited information about thephysical and mineralogical characteristics of some meteoroids fromcamera records using either the integrated brightness of the event orthe observed deceleration (Halliday et al. 1989).The Canadian Meteorite Observation and Recovery Project(MORP) was in operation in the Prairie provinces from 1971 until1982. The Innisfree (Alberta) meteorite was recovered as a directresult of MORP observations (Halliday et al. 1978). The MORP cameraswere optically very sophisticated, used film to record observations,and were expensive to build and to operate. One of the authors (RS)has developed an all-sky camera using inexpensive, off-the-shelfcomponents. One such camera is illustrated in Figure 1. Arrays offour (usually) such cameras have been installed at several locationsin North America. The Northern Alberta array in early 2001 consistedof a camera mounted on the roof of the Physics Building on the campusof the University of Alberta (hereafter UA); a camera at King’s CollegeObservatory, 18 km east of Edmonton (hereafter BM); another locatedat Alister Ling’s home in southwestern Edmonton (hereafter AL);and a fourth camera on the campus of Athabasca University, approximately130 km north of Edmonton (hereafter AU). The geographic coordinatesof the four cameras are listed in Table 1.Table 1.Northern Alberta All-Sky Camera ArrayCamera 1-UA University of Alberta (113° 30.4´ W 53° 31.5´ N)Camera 2-BM King’s Observatory (113° 10.1´ W 53° 30.8´ N)Camera 3-AL Ling Home (113° 34´ W 53° 28.5´ N)Camera 4-AU Athabasca University (113° 18.4´ W 54° 42.9´ N)Each camera consists of a Chungai Camera Model FC-08B,supported on a tetrapod approximately one metre above a 46-cmdiameter convex mirror of the type commonly mounted in the ceilingabove intersecting corridors in hospitals. The signal is sent to an arrayof three VHS video recorders, each of which operates for 8 hours insequence, to provide 24-hour coverage of the entire sky. A simpleheating cable mounted inside the hemispherical mirror preventscondensation and a build-up of snow except under very extremeconditions. The cameras have operated through three winters, andhave proven to be very robust; some minor problems have arisen dueto low temperatures, extremes of humidity, and tape and video recorderwear.The monochrome cameras used have a nominal minimumillumination of 0.08 lux at f/1.2 and a 1/3 inch CCD with 771 by 492Figure 1. – Sandia meteor camera on the roof of Athabasca University. Avideo camera is housed in the vertical white tube and aimed downward atthe convex mirror. Power and video cables run to recorders inside the building.approximately 7 micron pixels. A Computar TG0812FCS-3 lens, with8mm focal length and auto-iris control from f/1.2 to f/360, is pointeddown at the dome mirror, which is effectively hemispherical withradius 23 cm. This combination results in a limiting apparent stellarmagnitude of about –2 from a dark, rural site, and of approximately–3 from within Edmonton city limits. As a result, stars are not detectedon individual frames. The two brightest planets, Venus and Jupiter,have been recorded routinely. The stated magnitude limit easilyrecorded the fireball events of interest, since those that drop meteoritesare usually brighter than –10 magnitude. There is, however, a limitationin calibrating the images, that is, in converting a pixel coordinate onan image to a position (azimuth and altitude, or Right Ascension andDeclination) on the sky. It is possible to detect stars by stackingsuccessive frames from the videotapes and this provides known pointsfor direction calibration. For this we have also used the Iridium satellitesystem. The Iridium satellites produce “flares” when, for brief intervals,they are so positioned relative to Sun and a ground-based observerthat a reflection of sunlight is directed toward the observer. Iridiumflares are predictable: we have used data provided at www.heavensabove.com.Even with allowance for events lost due to inclementweather, there had been sufficient numbers of Iridium flares welldistributed over the sky to permit calibration of the system anddetermination of the location of events in the sky to an accuracy of0.5 to 1 degree. Despite our calibration prior to the event using thesemethods, we recalibrated, for this event, using stacked sky imagesthat showed bright winter stars near the path of the fireball. Thiswould not have been possible had the fireball been seen in a differentdirection.During approximately 12 months of operation preceding theJanuary 25 fireball, the Edmonton array recorded several brightmeteors. Numerous fireballs were subsequently recorded during theNovember 2001 Leonid meteor storm. The January 25 fireball wasthe only one recorded until the end of 2001 with characteristics ofsurviving meteoritic material that might easily be found on the ground.2. Observational DataOn the night of Thursday, January 25, 2001, at 19:21 MST (02:21,January 26, UT), several undergraduate student volunteers at the272JRASC December / décembre 2003

the fireball had traveled from NW to SE, passed close to the zenithnear Red Deer (113° 48´ W, 52° 16´ N), had a terminal burst SE ofRed Deer, and a projected fall zone north, or northeast, of the townof Big Valley (112° 46´ W, 52° 2´ N). Several individuals reportedfragments continuing very briefly after the terminal burst. A subsequentframe-by-frame analysis of the tapes confirmed the survival of materialafter the principal burst.The duration as determined from the tape records was 3.83 s(UA), 4.27 s (AL), 2.27 s (BM) and 3.13 s (DH). The BM record wasshorter than the others due to frost on the mirror.3. Camera CalibrationFigure 2. – Stacked image of fireball as seen from the University of Alberta.This composite of about 120 frames shows the fireball trajectory much as itwould have been perceived by the eye. In contrast, each frame shows thefireball “frozen” at each point along the path. The apparent width of the fireballtrail is due primarily to blooming in the camera. The lack of sky objects touse for calibration is apparent: only Venus (near bottom) and Jupiter (left offireball) are apparent in this image despite stacking. East is at the top andsouth is at the right.Campus Observatory of the University of Alberta in Edmonton visuallyobserved a fireball falling toward the southern horizon with a durationof a few seconds. Figure 2 gives an idea of the visual appearance ofthe fireball and some idea of the appearance of the taped output fromone of the all-sky video cameras. A check of the all-sky camera tapesat the nearby UA camera confirmed the event. Shortly thereafter,members of the public began to phone the universities and sciencecentres in Calgary and in Edmonton. Over the following month orso, we sent requests to radio stations and to newspapers requestingadditional reports. Good sky conditions and a suitable time of dayresulted in a large number of people over a wide geographic areaseeing the event.The event was recorded with the two all-sky cameras withinEdmonton (UA and AL) and with the one a short distance east ofEdmonton (BM). The AU camera experienced a tape failure severalminutes before the event. Several months earlier, one of us (Hladiuk)had begun to monitor a small portion of the sky with an ordinaryvideo camera pointed through a window of his home located in Calgary.Fortunately, the camera was pointed toward the north and this eventwas recorded. All visual observers in the Edmonton area agreed inplacing the event low toward the south and moving right-to-left (i.e.west to east), while all observers in the vicinity of Calgary placed itlow in their northern sky moving left-to-right (i.e. again, west to east).Observers in central Alberta (e.g. Red Deer, Ponoka) observed it highin the sky, in some instances close to the zenith, and moving towardthe southeast.Many observers reported a terminal burst, and this was alsoapparent in all the video records. Only a few individuals, located nearStettler, claimed to have heard a “sonic boom” (Hildebrand 2001).Most observers reported a visible duration of 2 to 4 seconds, whichwas confirmed on the videotapes. At its peak, the fireball was said byeyewitnesses to have been as bright as the Full Moon.From the initial analysis of the observations it appeared thatIridium satellite “flares” and stars on co-added (stacked) framesprovide the principal means for calibrating positions. At times, stellarobjects as dim as apparent magnitude +2 are detectable throughimage stacking, which builds up brightness where they are locatedwhile averaging out noise. The apparent motion of the stars due torotation of the Earth limits how much stacking can be done. Once astar’s “motion” shows up on the image, all advantage of stacking islost. Since the stars in the southern sky were needed for the Edmontonarea calibrations, in practice about 1000 images could be stackedand only the brightest winter stars emerged in the images. For aparticular event, the limitations to accuracy in determining thetrajectory of the fireball are the lack of reference objects near the pathand strong field curvature, especially close to the horizon. Luckily,this fireball passed near the bright southern winter stars, minimizingthe first problem. To counteract the second problem, a quadraticrelation between radial location of pixels and altitude above thehorizon was used.To further increase accuracy, for calibrating azimuths from thethree cameras in or near Edmonton, we used artificial lights near thehorizon. Their azimuths were determined via GPS relative measurements,aerial photo measurements, and surveyed measurements from thecamera sites.To calibrate DH’s video camera in Calgary, a 35-mm camerawas used to take calibration photographs from the same location.The 35-mm camera frames were digitally overlaid on video frames,with reference to ground-horizon features and to measuring staffs,to extract the required astrometric information.4. Trajectory SolutionTo solve for the atmospheric path of the fireball the technique ofBorovicka (1994) was employed. This algorithm uses an initial “bestguess”atmospheric path as a starting point for a least-squares solutionto sightlines from all stations. The program iterates the path until aminimum is reached in the deviations of the sightlines summed overall stations. Calibrated frames spaced approximately evenly acrosseach of the video records from stations AL, DH, BM, and UA hadfireball positional measurements made and employed for a firstsolution. Due to frosting of the mirror, the absolute BM astrometrywas noticeably poorer than at other stations; its positional informationwas dropped from the final solution. We do not expect this to significantlyaffect the final results, as the positional information from AL, BM,and UA are very similar, due to the closeness of these stations. Thusour solution uses AL, DH, and UA results to define the atmosphericpath. The program was executed for slight variations of input parametersDecember/ décembre 2003 JRASC273

and found to give a stable solution. Table 2 summarizes the result.The earliest point is defined by the start at AL as near as 90 km,somewhat above typical start heights for fireballs in this size range,but not unrealistic (Ceplecha & McCrosky 1976). The burst andendpoint both occurred at very typical altitudes for such a modestfireball. We expect, that had photographic methods been used withgreater sensitivity than our video equipment, the end height mighthave been determined as several kilometres lower than what wedetermined.Table 2.Computed Fireball TrajectoryAltitude Longitude (W) Latitude (N)Begin Point 87.0 ± 0.7 km 113.392 ± 0.007° 52.730 ± 0.009°Burst Point 37.8 ± 1.5 km 112.870 ± 0.12° 52.407 ± 0.060°End Point 35.8 ± 0.6 km 112.747 ± 0.005° 52.400 ± 0.007°Radiant altitude 39.2 ± 1.1° Radiant azimuth 135.1 ± 1.2°result, the best velocity profile was found by using only those sets ofpoints from AL and DH that had the smallest line-of-sight deviationsfrom the fireball path. The fits shown are quadratic and for velocityvs. time the curve has the form:v = ( 22 . 2 ± 1 )−( 0 . 563 ± 1 ) t− ( 0 . 720 ± 0 . 4 ) t2 .For unknown reasons, the velocities obtained from the UA tape showa large scatter, especially in the early sections of the trajectory. Thevarying error bars reflect in part distances from the cameras and inpart uncertainties in measuring the true position due to blooming,and we consider the velocity profiles to be fairly crude. Nevertheless,some quantitative information about the fireball can be obtainedfrom them.Our formal analytic fit suggests a velocity of 22.2 ± 1 km s –1 at90 km altitude. We expect some additional deceleration before thispoint, but cannot quantify the magnitude without knowledge of themass of the body. However, as estimated below, with a mass betweena few tens to (more likely) hundreds of kg, the correction to V∞amounts to

Table 3.Orbit of the January 26, 2001 MeteoroidV ∞ (km s–1) 22.2 ± 1.1V h (km s–1) 39.5 ± 0.9α R (J2000.0) 313.0 ± 1.9δ R (J2000.0) 56.8 ± 1.4α G (J2000.0) 307.9 ± 1.9δ G (J2000.0) 53.5 ± 1.5a (Semi-Major axis; AU) 3.69 ± 1.14e (eccentricity) 0.74 ± 0.08q (perihelion distance; AU) 0.957 ± 0.005i (inclination; degrees) 27.3 ± 1.7ω (argument of perihelion; degrees) 159.1 ± 1.9Ω (Longitude of Ascending node; J2000) 306.188 ± 0.001Q (Aphelion distance; AU) 6.4 ± 2.2θ (True anomaly; degrees) 20.9 ± 1.9Time since perihelion (days) 15 ± 2aphelion may well be inside Jupiter’s orbit, as is the case for mostmeteorite-producing fireballs (Wetherill & Revelle 1981). Comparisonof this orbit with known orbits of near-earth asteroids, comets, andmeteoroids reveals no close associations despite there being severalthousand meteoroid orbits resulting largely from MORP. Comparisonswere done using the D criterion (Ceplecha et al. 1998) where a valueover 0.1 would have indicated a significant similarity to a given orbit.7. Field SearchesThe brightness, terminal burst, and phenomena reported by witnessessuggested early on that meteoritic material had fallen (the orbit andmass, determined later, support this). The predicted fall zone wasnear the village of Big Valley, approximately 75 km east-southeast ofthe city of Red Deer. Three field searches were conducted in April2001, after the winter’s accumulation of snow had melted, and beforesignificant new vegetative growth. The area is typical of western prairieagricultural lands consisting largely of open and hilly fields used forgrazing cattle and for the growing of crops. Stubble from the previousyear’s crops plus a scattering of small stones covers the open ground.A significant fraction of the stones are smooth, dark clay stones ofthe type commonly misidentified by the public as being meteorites.There are scattered small swamps, small stands of trees, and a fewoil wells and associated hardware.A total area of approximately two km 2 was searched by systematicsweeps, but no meteoritic material was found. Local residents, manyof whom had observed the fireball, were alerted to the possibility ofmeteorites being found, but no finds were reported during, or following,our search.8. Lessons Learned and Developments for the FutureOne should not underestimate the time required to assemble andcalibrate equipment, and the difficulty in identifying suitable locationsand local operators. We knew in advance that the spacing of theEdmonton-area cameras was not good. For the purpose of determininga reliable trajectory and fall zone, the cameras should be spaced 50to 100 km apart. In 2001, the three Edmonton-area cameras lay alonga roughly east-west line of length 20 km, or so. The Athabasca Universitycamera is well separated (north-south) from the others, but was notfully operational on the night of interest and would, for this event,have served only to confirm the azimuth obtained from the others.The positions of cameras in their present form necessitate onsitemanagement (e.g. for the purpose of changing video tapes daily).Automatic, non-mechanical operation is preferred. To that end, othersand we are developing software for event detection through flashmonitoring. That is, successive images are automatically comparedand changes above a certain threshold from one to the next triggerthe storage of a sequence of images for later analysis. With digitizationdirectly from video, storage on a hard drive, and linking of localcomputers to a central site, one person could operate an array ofcameras. Local events such as airplane flyovers could be distinguishedfrom fireballs through inter-comparisons of records from two or moresuitably sited cameras.Substantial effort was put into calibrating the images, but amore refined calibration is desirable. Much of the work to calibratethe cameras took place after the event. It is important to mount thecamera rigidly in what will be its permanent location, and to calibratefrequently using planets, stars, and Iridium flares widely distributedover the sky. Calibration of altitude close to the horizon is particularlydifficult, but very important since most fireball events are likely tobe distant from the camera and, hence, close to the horizon. Evenwith good calibration, the angular resolution of the cameras will notbe better than 0.5 to 1 degree. Any lower resolution would precludedetermination of reliable velocities.As noted previously, the original video cameras are too insensitiveto record any but the brightest planets, and the brightest stars canonly be seen by stacking images. Newer, often less-costly low-lightvideo cameras are becoming available, as are low-cost wide-anglelenses suited to meteor detection (Horne 2003). Cameras should bereplaced as newer, technically superior devices become available.Eyewitness reports are open to interpretation when they referto local everyday events such as road accidents, but even more sowhen they refer to a sudden once-in-a-lifetime event such as a brilliantfireball. Eyewitness accounts have greatest value when obtained underthe track or near the endpoint. The details presented by eyewitnessescan change with time, so the earlier one collects such reports themore accurate they will likely be. Objective instrumental records aremuch preferred, and should, in general, carry the greatest weight.9. ConclusionsThe mass of the meteoroid at atmospheric entry is estimated to havebeen tens to hundreds of kilograms. There would have likely beenaround a kilogram of surviving meteorites, but none were found infield searches in the likeliest location.The orbital determination places the meteoroid in a typicalApollo orbit with, however, a higher-than-normal inclination.With improved calibrations, better camera mounts, a widerdistribution of the cameras in north-central Alberta, and the installationof a camera network in southern Alberta, we anticipate greater successin analyzing future fireball events, and improved prospects for therecovery of meteorites. We are waiting patiently for Nature to producethat next event.December/ décembre 2003 JRASC275

AcknowledgementsThis research was supported in part by operating grants from theNatural Sciences and Engineering Research Council of Canada toBrown, Hube, and Connors. Fieldwork was conducted in cooperationwith Alan Hildebrand of the University of Calgary and partly fundedby the Meteorites and Impacts Advisory Committee of the CanadianSpace Agency. We thank J. Borovicka for providing the program usedin determining the fireball trajectory, and Z. Ceplecha for providingthe software used in determining the orbit.ReferencesBorovicka, J. 1990, Bull. Astron. Inst. of Czech., 41, 391Ceplecha, Z., & McCrosky, R.E. 1976, J. Geophys. Res., 81, 6257Ceplecha, Z., Borovica, J., Elford, W.G., ReVelle, D.O., Hawkes, R.L.,Porubcan, V., & Simek, M. 1998, Sp. Sci. Rev., 84, 327Hildebrand, A. 2001, personal communicationHalliday, I., Blackwell, A.T., & Griffin, A.A. 1978, JRASC, 72, 15Halliday, I., Blackwell, A.T., & Griffin, A.A. 1989, JRASC, 83, 49Horne, J. 2003, Sky & Telescope, 105, Number 2, 57 (February, 2003)Spurny, P. 1997, Pl. Space Sci., 45, 541Wasson, J.T. 1985, Meteorites: Their Record of Early Solar-SystemHistory (W.H. Freeman: New York)Wetherill, G.W., & Revelle, D.O. 1981, Icarus, 48, 308Martin ConnorsCentre for Science, Athabasca University1 University DriveAthabasca AB T9S 3A3Martin Connors is an Associate Professor at Athabasca University, recently named as Canada Research Chair in Space Science, Instrumentation,and Networking. His main interests are in planetary astronomy and space physics.Peter Brown is an Assistant Professor and holds the Canada Research Chair in Meteor Science at the University of Western Ontario. He hasrecently started the NEAPS (Near-Earth Asteroid Physical Studies) program using the UWO Elginfield 1.22-m telescope.Douglas P. Hube is now Professor Emeritus in Physics at the University of Alberta. His studies focus on binary stars. The U of A Devon Observatorynow hosts an automated meteor camera.Brian Martin is a Professor at The King’s University College in Edmonton. His main astronomical interest is precision photometry of cataclysmicvariable stars. The King’s College Observatory now hosts an online automated meteor camera.Alister Ling is an active amateur astronomer in the Edmonton Centre and a regular contributor to astronomical publications. Due to his fulltimejob at Environment Canada he is much sought after for detailed weather predictions for observing.Donald Hladiuk, an active amateur astronomer in the Calgary Centre, runs his own video monitoring system that contributed to this article.His employment as a geologist at Conoco Canada has an astronomical connection through the Steen River impact structure, a trap for oil andgas.Mike Mazur is a graduate student in Geology and Geophysics at the University of Calgary. He has been involved with meteoritic events includingthe Tagish Lake fall and the finds of the Prairie Meteorite Search.Richard Spalding, a senior engineer at Sandia National Laboratories, specializes in satellite sensor research, developed the all sky camerasused for this article, and has provided these cameras to several groups in North America. His own network operates under the clear skies ofNew Mexico.276JRASC December / décembre 2003

CANADIAN THESIS ABSTRACTSCompiled By Melvin Blake (blake@ddo.astro.utoronto.ca)A Wide-Field Imaging Survey of Low-Redshift Galaxy Clusters By WayneA. Barkhouse (wbark@head-cfa.harvard.edu), University of Toronto,Ph.D.This thesis presents the results from a comprehensive study of 26low-redshift galaxy clusters in order to study the radial dependenceof various cluster properties. The observations were acquired usingthe 8k mosaic camera on the 0.9-m KPNO telescope. This datasetwas supplemented by 43 clusters from the survey of López-Cruz(1997), and an additional 2 clusters from Brown (1997). Thus, a totalsample of 71 clusters covering a redshift range from ~0.01 to 0.20 wasavailable for analysis. The dynamical radius of each cluster (r 200 ) wasestimated from the photometric measurement of cluster richness(B gc ). The cluster galaxy colour-magnitude relation (CMR) was usedas a tool to minimize the inclusion of contaminating backgroundgalaxies by selecting galaxies relative to this relation. The luminosityfunction (LF) of individual and composite galaxy samples wereconstructed via the statistical subtraction of background galaxies. Arobust method of comparing LFs for a variety of galaxy samples overa range of cluster-centric radius was presented. The general shape ofthe LFs were found to correlate with radius in the sense that the faintendslope was generally steeper in the cluster outskirts. Colour selectionof galaxies into a red sequence and blue population indicates thatthe blue galaxies become fainter toward the cluster central region.This result supports the scenario that infalling field galaxies havetheir star formation truncated by some dynamical process. Theconstruction of a non-parametric dwarf-to-giant ratio (DGR) andthe blue-to-red galaxy ratio (BRR), allowed the investigation into thechange in these parameters with various cluster properties. The radialdependence of the DGR and BRR suggests that blue dwarf galaxiesare tidally disrupted in the inner cluster environment or fade andturn red. The red, mainly nucleated, dwarf galaxies remain relativelyunchanged with respect to cluster-centric radius, while giant bluegalaxies have transformed into their red galaxy counterparts. Theseresults provide support for the model proposed by López-Cruz et al.(1997) to explain the formation of cD and Brightest Cluster Galaxyhalos in which dwarf galaxies get tidally disrupted in the inner clusterregion.W4 Revisited: A Chimney Candidate in the Milky Way Galaxy ExploredUsing Radio Continuum and Polarization Observations By JenniferLorraine West (westjl@cc.Umanitoba.CA), University of Manitoba,MSc.Compelling evidence for the existence of a fragmented superbubbleabove W4 that may be in the process of evolving into a chimney hasbeen found. High latitude extension fields above the W3/W4/W5star forming region have been processed at both 1420 and 408 MHz(21 and 74 cm) Stokes I total power as well as Stokes Q and U polarization.These observations reveal an egg-shaped structure with morphologicalcorrelations between our data and the Hα data of Dennison, Topasna& Simonetti (1997, ApJ 474 L31), as well as evidence of breaks in thecontinuous structure. Assuming an estimated distance of 2.3 kpc,the egg structure measures ~165 pc wide and extends ~240 pc abovethe mid-plane of the Galaxy. In addition the polarized intensity imagesshow depolarization extending from W4 up the walls of the superbubbleproviding strong evidence that the observed continuum and Hαemissions are at the same distance as the W4 region.A temperature-spectral-index map indicates that there are nohigh-energy losses in the region via synchrotron emission. This impliesthat energetic cosmic rays retain sufficient energy to escape into theGalactic halo. In addition the rotation measure in the region has beencalculated allowing an estimate of the line of sight magnetic field(B // ) in the region to be determined. We find B // =9 ±8 µG assuminga wall thickness of 20 pc or B // = 13 ± 11 µG assuming a wall thicknessof 10 pc and directed towards the observer.In addition, some interesting features appearing in the polarizationand 408 MHz datasets are examined. These features are not likelyrelated to the W4 superbubble.Jennifer West is currently a Ph.D. candidate at the University of Manitoba.Wayne Barkhouse, Editor-in-Chief of the Journal, is currently a postdoctoralresearcher at the Harvard/Smithsonian Center for Astrophysics.December/ décembre 2003 Journal of the Royal Astronomical Society of Canada, 97: 277, 2003 December 277

Education NotesRubriques pédagogiquesWHAT IS SIDEREAL TIME AND WHAT IS IT GOOD FOR?by William Dodd, Toronto Centre (wwdodd@sympatico.ca)IntroductionEach day, as viewed from the surface of the Earth, the Sun, and thestars rise in the east and set in the west, however, the stars appear tomove across the sky a little faster than the Sun, and each day theconstellations advance towards the west another 1° ahead of the Sun.After a whole year the constellations return to their starting positions.The different motions of the Sun and stars give rise to two differentsystems of time. The daily rotation of the Earth relative to the positionof the Sun is used to define solar, or civil time. The daily rotation ofthe Earth relative to the stars is used to define sidereal time.Sidereal TimeAs viewed from far above the North Pole, a sidereal day begins whenthe vernal equinox crosses an observer’s upper meridian and endswhen the vernal equinox next crosses that meridian. During a siderealday the Earth rotates 360° around its polar axis.From the same viewpoint, a civil day begins when the Sun crossesan observer’s lower meridian and ends when the Sun next crossesthat meridian (i.e., a civil day begins at midnight). During a civil daythe Earth rotates just under 361° around its polar axis and also revolvesjust under 1° in its orbit around the Sun. The extra time required forthat degree of revolution makes the civil day about 4 minutes longerthan a sidereal day. Over a complete year that time difference accumulatesto one complete rotation of the Earth. During a civil year the Sunpasses overhead 365 times while the vernal equinox passes overhead366 times.Since the sidereal day is the interval of time between two successivepasses of the vernal equinox across any observer’s meridian, the siderealtime at any location is equivalent to the hour angle of the vernal equinox.This is the essential property of sidereal time that is useful to astronomers.Sidereal time and civil time at Greenwich, England (UniversalTime or UT) match up with each other about September 21. Afterthat date, sidereal time edges ahead an extra 3 m 56 s each day. At thespring equinox, sidereal time is 12 h ahead of UT. By the next autumnalequinox the times match up again.Equatorial CoordinatesThe equatorial system of Right Ascension (RA) and Declination (Dec)is analogous to terrestrial longitude and latitude and offers at leastthree distinct advantages to astronomers.1. The RA and Dec of a celestial object are unique and relativelyconstant over decades. Most star charts and catalogues givestellar coordinates in RA and Dec.2. As Earth’s rotation carries a star across the sky, its Dec coordinateremains constant.3. If a telescope has an equatorial mount and is correctly oriented,then its RA axis is parallel to the Earth’s axis of rotation. Once acelestial object has been located with such a telescope, the objectcan be kept in view by a simple westward rotation about the RAaxis that counteracts the Earth’s rotation.Uses of Sidereal TimeSidereal time and RA are both defined relative to the vernal equinox.These definitions lead to an important result:Your Local Sidereal Time (LST) is the same as the RA of any object onyour meridian.Once you have located Polaris and the celestial equator, you can useLST to quickly construct a mental grid of RA and Dec for the sky.Suppose at a particular moment your LST is 12 h 00 m . Then youautomatically know that all objects along your meridian have an RAof 12 h 00 m . You also know that all the objects one hour, or 15°, towardsthe east have an RA of 13 h 00 m . And all the objects one hour towardsthe west have an RA of 11 h 00 m . Dec can be estimated relative to thecelestial equator.The RA of an unknown object can be determined by recordingthe time of its transit across your meridian. The sidereal time of thatmoment equals the RA of the object. The RA of an object can also beestimated by measuring its hour angle (HA): RA = LST + HA.Knowing that the RA of a transiting celestial object is the sameas your LST, you can make better use of star charts and catalogues.Once you know your LST, you can go directly to the star chart thatshows the sky above your head at that moment. Astronomical cataloguesusually list objects by increasing RA. Once you know your LST, youcan immediately locate the objects in a catalogue that are potentiallyobservable at your location at that moment.Using the equation HA = RA – LST, you can calculate the HAof any object once you know its RA and your LST. With the ability topredict the hour angle of a celestial object at any given time, you canplan an observing session to proceed from object to object as theymove into convenient positions for viewing. With this approach youcan minimize the time spent searching for objects and adjusting278Journal of the Royal Astronomical Society of Canada, 97: 278-279, 2003 DecemberDecember / décembre 2003

equipment for different viewing angles, and maximize the time spenton target.To locate a celestial object with an aligned equatorial telescope,all you have to do is set the object’s HA and Dec, and the object shouldautomatically be in your finder scope.How Can You Determine the Sidereal Time?There are a variety of methods for determining sidereal time. In allcases, you need the date, the longitude of your location, and thestandard time in your time zone. A particular method may refer toLocal Sidereal Time (LST), Local Mean Sidereal Time (LMST), orLocal Apparent Sidereal Time (LAST). In this section, no distinctionis made among these terms. For precision applications of siderealtime, readers should refer to texts, or Internet searches on astrometry.1. You can calculate Local Mean Sidereal Time (LMST) using theformulas provided on page 41 of the Observers Handbook 2003(RASC). A programmable calculator can be set up to performthese calculations without too much difficulty. Finding LMSTdepends on Greenwich Mean Sidereal Time (GMST). Instead ofcalculating GMST, you can read the precise GMST from an onscreendigital clock at home.att.net/~srschmitt/clock.html.2. The U.S. Naval Observatory at tycho.usno.navy.mil/what.html provides a menu item “Compute Local Apparent SiderealTime” that calculates LAST for the moment when the “Submit”button is pushed. To take advantage of the accuracy available,you need to know your own longitude precisely.3. You can harness your own computer’s calculating power togenerate a sidereal clock. Three of the many astronomical sitesthat provide free sidereal clock software are listed here:• astronomy.physics.tamu.edu The Learning Observatoryat Texas A&M University. Look under “downloads/astronomyclock.”• asds.stsci.edu Astronomical Software & DocumentationService (funded by NASA)• www.radiosky.com The Radio Sky site also provide lots ofother information for radio astronomers.4. You can use a planetarium program, such as Starry Night, todetermine the RA of the meridian for any given moment at anylocation. That RA is also the LST for that moment at that location.5. You can purchase a sidereal clock. Search on the Internet underthe topics “sidereal clocks horology.” One site with sidereal clocksfor sale is www.bmumford.com/clocks/sidereal. Once asidereal clock is correctly set and hanging on your wall, you havesidereal time available at a glance.6. You can estimate LST by constructing a simple graph. As shownin the figure, mark the months on the horizontal axis and thehours from 0 to 24 on the vertical axis. Then estimate the locationsof the points A (Sept 21, 0 h ) and B (Sept 21, 24 h ). The line ABdescribes Greenwich LST (GLST) at midnight for any day of theyear. To find your LST, first use the graph to estimate the GLSTfor a particular date. Then express your longitude (L) as a timein hours. The quantity GLST – L will provide an estimate of yourLST at the civil time corresponding to 12 – L. You can add orsubtract civil hours to estimate LST for any other time duringthat day.7. For a simple, but temporary, sidereal clock simply set any digitalclock to the 24-hour mode and then enter the sidereal time usingone of the methods listed above. Your standard clock will onlylose 1 minute of sidereal time for every 6 hours of observing.SummarySidereal time depends on the position of the vernal equinox, the date,the time, and your longitude. LST can be found in a variety of ways.Once you have determined your LST, that time provides the RA of allcelestial objects on your meridian. That knowledge can assist you inmaking full use of your astronomical resources and equipment.NotesDuncan Steel is an Australian astronomer and has recently writtena book, Marking Time: The Epic Quest to Invent the Perfect Calendar(Wiley, 2000). It is recommended if you are interested in reading moreabout the history and definitions of time.Your comments on this article are welcome. If you have commentson any of the items that have appeared in recent Education Notes,send an e-mail message. If there is a topic that you would like to seediscussed in this column, let us know.William Dodd is a member of the Toronto Centre. He is a retired mathematics teacher with particular interests in the educational andhistorical aspects of astronomy.December/ décembre 2003 JRASC279

THE STORY OF SKYWAYS: THE RASC’S ASTRONOMY HANDBOOK FOR TEACHERSby Mary Lou Whitehorne, Halifax Centre (mlwhitehorne@hfx.eastlink.ca)“You, my dear,” she declared, “should write a book!” I stared back at her,sure that she was speaking to someone else, but Margaret Myles wasaddressing me. There were only the two of us in the room. It was the endof the day and all the other teachers who had spent the day in the Starlabhad already left. She continued, “Nobody has ever explained astronomyto me before so that I could understand it. You made it so easy and somuch fun. You have a real gift. You should use it.”I thanked her for the compliment and together we packed up theStarlab, left the school, and went our separate ways. It had been a goodworkshop. Although I dismissed her words at the time, they kept comingback to haunt me. They came from other teachers at other workshops.Those words haunt me still, for they were the genesis of Skyways.Myles is one of many remarkable teachers with whom I have hadthe pleasure of working over the past 14 years. Full of life, energy, humour,and fun, I can only imagine what a vibrant place her classroom must be.As I worked hard to make Skyways into something that teachers wouldfind helpful, I thought of the many “Margarets” in Canada’s classroomsand I wrote for them. The formula seems to have worked reasonably well,since the teacher feedback from last year’s draft version of Skyways wasvery positive. Teacher comments and suggestions guided all of the changesand additions, and reshaped the book into its present form.Skyways is an astronomy handbook for teachers. It is quite differentfrom anything that the RASC has ever done before. The Society is usedto producing publications for its own members and for amateur astronomersand astronomy enthusiasts. We know that audience and its needs quitewell. The Skyways project is taking the Society into territory that is notquite so familiar.The RASC has long worked with schools, teachers, science centres,planetaria, museums, and youth groups to promote and enhanceastronomy education. For many educators, the RASC is an importantresource. We have been very successful in these informal efforts and haveestablished a solid reputation as a credible and effective educationalresource. Skyways aims to build on our existing, firm educational foundationby taking our expertise into the more formal environment of the curriculumdrivenclassroom.Skyways is national in scope. There is a new science curriculum inCanada called the Common Framework of Science Learning Outcomes,published by the Council of Ministers of Education, Canada. 1 Thedocument is sometimes called the “pan-Canadian Curriculum,” and isthe parent document from which most provinces and territories havedrawn their own curricula. These new curricula have been introducedacross the country and teachers are now teaching more astronomy thanbefore. It is showing up at more grade levels, and in more depth and detail.My own experience, and the experience of many RASC ‘s members,is that there are plenty of teachers who are looking for help with the newcurriculum. There are very few Canadian resources to help them. Skywaysis the RASC response to that need. Skyways is unique in that it uses thepan-Canadian Curriculum to govern its content. Skyways addresses eachof the specific, astronomy requirements of the new Canadian sciencecurriculum.Skyways aims squarely at the needs of Canadian teachers, and isorganized with them in mind. The first section of the book deals withthe required curriculum objectives and includes some pedagogy toimprove the teacher’s comfort level. Skyways is one-stop-shopping forCanadian teachers looking for resources to help them with their astronomyunits.The book is organized by topic and grade-level grouping. Thereis a handy one-page chart that lists activities according to topic andgrade-level-appropriateness. There is a section on common misconceptionsand how to dispel them and replace them with correct ideas.The second and third sections of the book are devoted toelementary/middle-school grades, and high-school grades, respectively.These sections contain background information, classroom and observingactivities, and student worksheets. Each topic and activity refers theteacher to additional online resources, if the teacher wants to explorefurther. The fourth section of the book is a resource section with FAQs,a book list, Web resources, Canadian observatories and planetaria, andCanadian contributions to astronomy.The layout and illustrations for Skyways are professionally done.The book is very attractive inside and outside. Its look speaks clearly forthe quality that can be found between the covers. The illustrations, tables,and graphs make the material clear, and the overall design allows textto flow smoothly for fast, easy reading. The page design, typeface, andgraphics have excellent eye-appeal. The 8.5 × 11-inch format with spiralbinding makes it easy for teachers to photocopy student worksheetsand other pertinent pages, as they choose. The tone is friendly and downto-earth.Everything about the book is governed by the desire to meetthe needs of teachers, and to make astronomy fun and accessible at thesame time.There are almost 300,000 teachers in Canada. 2 We have all heardthem ask for help. We continue to answer with classroom visits, observingsessions, and other activities. Now, with Skyways, we can strengthen oureducational partnerships. The RASC is now set to have a tangible,targeted, educational presence in Canadian classrooms.Yes, Margaret, I was paying attention. We should never underestimatea teacher’s influence. Skyways is proof positive of what happens whensomeone takes a teacher’s words to heart.Skyways is available for $19.95 Cdn + GST, including shipping(RASC members $16.95 Cdn + GST), and can be ordered through theRASC by either:Phone: (888) 924-RASCFax: (416) 924-2911E-Mail: orders@rasc.caWeb: www.store.rasc.caMail: RASC Orders, 136 Dupont Street, Toronto ON M5R 1V2 CanadaMary Lou Whitehorne has over 14 years of astronomy educationexperience working with teachers and students of all grade levels inclassrooms, workshops, planetaria, conferences, and summer institutes.She is the author of Skyways.1 Common Framework of Science Learning Outcomes, Council of Ministers of Education, Canada, 1997, www.cmec.ca.2 Statistics Canada, Full-time Teachers, www.statcan.ca/english/Pgdb/educ22a.htm.280Journal of the Royal Astronomical Society of Canada, 97: 280, 2003 DecemberDecember / décembre 2003

Across the RASCdu nouveau dans les CentresSociety News/Nouvelles de la sociétéby Kim Hay, National Secretary (kimhay@kingston.net)National Council MeetingsAt the time of the writing of thisnote, there will be a NationalCouncil meeting on October 25,2003 (NC035). Details of that meetingwill be in the next Society News. A changeof venue for that meeting will bring usto the Ontario Science Centre. This year,once again, the Toronto Centre is extendingan invitation to the Council to observeat the Carr Observatory, Beaver Valley(near Collingwood, Ontario).October also marked the launch ofthe new RASC publication Skyways. Thishas been a project for the EducationCommittee and author Mary LouWhitehorne for a few years now, andcopies are available online at the RASCeStore at www.store.rasc.ca.A note from the Membership &Promotion Committee:As you may already know the VancouverCentre created a wonderful keepsake ofthe Royal Centenary year as part of thisyear’s GA celebrations. The Royal CentenaryCoffee Mug is an excellent-quality drinkingvessel with the Commemorative logoemblazoned in full colour.In 2003 the RASC celebrated its 100thanniversary as a Royal Society. A limitedquantity of commemorative mugs isavailable with a special design celebratingthe Centenary. These dishwasher-safeceramic mugs have the Royal Centenarylogo on both sides (front and back). Perfectfor home, office, or observatory.The cup is 9.5 cm high (3.75-inch)and holds 300 ml (10 fl. oz). The price is$10.00 Cdn. (price includes postage andhandling within Canada. GST/HST willbe added as appropriate).Upcoming EventsThis is a reminder to all Centres andindividuals for any of the RASC awardslisted in the table below that nominationsshould be sent to the National Office byDecember 31, 2003. For an expandeddescription of the awards, visitwww.rasc.ca/award/.C.A. Chant Medalfor significant astronomical workKen Chilton Prizerecognition of significant astronomicalwork carried out duringthe yearSimon Newcomb Awardfor literary achievementThe Service Awardfor contributions to the RASC overa minimum 10 year spanOn a further note, a notice was sent toNational Office on September 19 fromthe Chelminski Gallery in Chelsea, London,in regards to their bust of Sir Isaac Newton.Dear Sirs/Mesdames,Please find attached a photo &description of the fine white marble18th Century bust of Sir Isaac Newtonwhich has recently arrived at the Galleryhere, and which I thought you wouldbe interested to see.This is after the original by Roubiliacfor the Royal Society, repeated at TrinityCollege, and may also have a connectionwith Sir William Herschel having beenacquired from Datchet House, closeto where he lived, and home of theNeedham Family - Earls of Kilmorey& Barons of Armagh.If you would like any furtherinformation, please do not hesitate tocontact me.Yours truly,Hilary ChelminskiChelminski Gallery Antique Sculpture& Garden Ornament616 King’s Road, Chelsea, LondonSW6 2DU. U.K.Tel: 020 7384 2227Fax: 020 7384 2229www.chelminski.comEmail: hilary@chelminski.comNo: 292Height: 28 inch (71 cm)A WHITE MARBLE BUST OF SIR ISAACNEWTON (1642-1727) AFTER LOUISFRANCOIS ROUBILIAC (1695-1762)English – Late 18th CenturyInscribed: NEWTONProvenance: Datchet House, Nr. Windsor.December/ décembre 2003 JRASC281

“A white marble bust of Sir Isaac Newton,mounted on a circular socle base, afterthe original made for the Royal Societyin 1738 by Louis Francois Roubiliac.Another version, signed and dated 1751,is in the Wren Library, Trinity College,Cambridge.“Louis-Francois Roubiliac, the Frenchbornsculptor, settled in London in the1730s, and made his reputation with afull-length seated statue of the composerHandel (now in the Victoria & AlbertMuseum), remarkable for its livelyinformality, and quickly became recognisedas the most brilliant portrait sculptor ofthe day. He is generally regarded as oneof the greatest sculptors ever to work inEngland, certainly the greatest of hisperiod, having both a vivid imaginationand being a superb craftsman.“The original Bust was madewithout a base — a square socle beingsupplied separately at the request ofthe Royal Society. Roubiliac’s terracottamodel is at the Royal GreenwichObservatory. Another marble versionwith a round socle is at the RoyalAstronomical Society, Burlington House,and a marble version by Edward HodgesBaily, dated 1828 (1751), is in theNational Portrait Gallery.“There are indications that theSculptor of this present Bust may havehad an association with Joseph Nollekens(1737-1823). It is also possible that thisBust may have a connection with SirWilliam Herschel (1738-1822), the RoyalAstronomer and discoverer of Uranuswhose name is often linked withNewton’s. He lived in Datchet in the1780s before later moving to OldWindsor. Datchet House was home tothe Needham Family, Earls of Kilmorey,and Barons of Armagh. Herschel wasalso involved with the establishmentof the Armagh Observatory, in 1790.”Since this year is coming to a close,and another soon to start, I would liketo wish everyone in the RASC a warm,clear, and Happy Holiday Season.Clear SkiesInternational Astronomy Day 2004 is Saturday April 24by Bruce McCurdy, National Astronomy Day Coordinator (bmccurdy@teusplanet.net)On that day, professional andamateur astronomers all over theworld bring the Universe to thepublic, through observing sessions, displays,and information booths in malls, sciencecentres, and planetaria. The RASC joinsgroups from nearly 30 countries incelebrating International Astronomy Day.The 2004 spring sky will offer acornucopia of delights for a publicobservingsession. The pictured chartshows the panorama visible fromEdmonton, Alberta 30 minutes aftersunset on April 24, at which time theMoon and four naked-eye planets will allbe between 30° and 45° altitude. Thewestern horizon is depicted by the curveat lower right. Particulars for other locationsacross the country will be very similar.Centres wishing to plan additionalor alternative observing sessions mayalso want to consider Saturday, March27. On that date Mercury will also bereadily visible in its best evening apparitionof the year, while the outer planets willbe bigger, brighter, and further from theSun. Venus and Mars will straddle thePleiades. Also, Standard Time will stillbe in effect, with sunset occurring almosttwo hours earlier than during DaylightSaving Time.Centres planning their local A-Daymay wish to consider the Transit of Venusas an appropriate theme for 2004. Muchmore information is available on the RASCWeb site, at www.rasc.ca/activity/astroday/. Please contact the writer toadvise of your Centre’s plans and to requestfurther ideas and assistance.282JRASC December / décembre 2003

Unveiling Asteroids:International Observing Project andAmateur–Professional Connectionby Mikko Kaasalainen, Rolf Nevanlinna Institute, University of Helsinki (mjk@rni.helsinki.fi)AbstractIreview methods (other than spacecraftflybys) of obtaining detailedinformation on the shapes, spin states,and other characteristics of minor planets.Non-directly resolvable asteroids canactually be imaged with these methodsby making use of various data sourcesand modern mathematical techniques.Especially photometric observations playa key role in the construction of a largesample group of models representing theasteroid population. Amateur observers,in their turn, have an important andnecessary role in providing suchobservations.1. IntroductionAsteroids and comets form the largestand, perhaps paradoxically, the least wellknownpopulation of celestial bodies inour solar system. The shortage of detailedinformation is mainly due to the fact that,because of the large interplanetarydistances, disk-resolved images can beobtained only of a limited number ofthese targets. Nevertheless, our view ofthis population has started to changedramatically over the past few years.Spacecraft images and detailed radarobservations, though very limited in theirability to cover the asteroid population,have already revealed to us that asteroidscome in just about all possible shapes(from spheroids to “dogbones”),configurations (from single bodies tocontact or separate binaries or satellitesystems), and structures (rubble piles,solid or fractured rocks, smooth orbombarded surfaces). The need for detailedinformation on a large sample of asteroidsis thus now pressing, and fortunately, itturns out that there are rich data sourcesreadily available. I will discuss below howthe present golden age of asteroid researchapplies also to amateurs, who now have,thanks to modern equipment and CCDcameras, a remarkable opportunity toparticipate in important scientific research.In addition to their importance incompleting the big picture of our solarsystem today, asteroids also carry importantinformation from the past. They are, ina way, dinosaurs of the solar system.Unlike planets that are thoroughly mouldedby various physical and geological processes,asteroids still contain material from theprimordial stages. By studying theircomposition, structure, shapes, rotationalstates, and orbits, we can reconstructmuch of the history of our system.2. Asteroid modelsfrom remote sensingDisk-resolvable direct images of asteroidsare available only from flybys (e.g. Thomaset al. 1994, 1996; Zuber et al. 2000); thereare some very crude low-resolutionsnapshots of the largest few asteroidstaken with the Hubble Space Telescope,but we cannot expect much betterresolution because of physical limitations.Other methods of obtaining information(including radar) are indirect, so theyconstitute inverse problems. We neverproperly see the target, so we have to finda way of making a full model of it thatexplains the observations. In fact this isprecisely what our brains do every daywith the data from our senses, includingimages, so in that sense we all solve inverseproblems all the time — we are justaccustomed to doing it with instinct andexperience, not mathematics. When wehave to invoke mathematics, the first stepis to solve the direct problem, that is, togive detailed mathematical and physicalrules accurately describing how theobserved quantities are determined bythe parameters describing the target andthe observational circumstances. In ourcase, we are primarily interested in therotational state, shape, and surfacecharacteristics of the target. The secondstep is to check whether we can trace thisoriginally one-way path back to the startingpoint. Usually it turns out that this cannotbe done without some constraints and/oradditional information, so the secondstep is considerably harder than the first.This is why inverse problems are a veryactive field of study in applied mathematics.The third step is to make the actualbackward trip for each target, startingwith the real instrument readings andending up with model figures and imageson the computer display.2.1 Photometric dataA previously much unused but major andeasily available source of information onsmall solar system bodies consists of theirphotometric light curves, that is,measurements of their total brightnessesthat vary as the viewing/illuminationgeometry changes. We can now well saythat the resolving capacity of light curveinversion lies, roughly speaking, betweenspace telescope and radar, and its rangeextends from near-Earth to Jupiter Trojanasteroids (Kaasalainen et al. 2002c).Let us first write the mathematicalmodel describing an asteroid’s brightness(Kaasalainen & Torppa 2001). This is doneby integrating over all visible andDecember/ décembre 2003 JRASC283

illuminated surface patches of infinitesimalarea ds. In a coordinate frame fixed tothe asteroid, the contribution dL to thetotal brightness L = ∫ dL is, at some pointr on the surface (ignoring the trivialdistance-squared factors)dL S ( r), ( r) v( r)ds= [ ]0 ,(1)where ϖ and S are the albedo and the socalledlight-scattering model of the surface;µ = E · n(r) and µ 0 = E 0 · n(r), where Eand E 0 are, respectively, unit vectorstowards the observer (Earth) and the Sunat the moment of observation, and n(r)is the surface unit normal. Lambert’s law,for example, is S L = µµ 0 , while the Lommel-Seeliger law is S LS = S L /(µ + µ 0 ). Note thatL is given in intensity units rather thanmagnitudes. In practice, brightness changesare ascribed almost completely to shape;potential albedo variegation over thesurface can be separated from shape tosome extent, but from physicalconsiderations and spacecraft images wecan expect such effects to be quite small.The integral is in practice computed bytessellating the surface into small planarfacets and replacing the integral by a sum.In the inverse problem we solve for theparameters defining such a surface (i.e.r) by minimizing with suitable optimizationprocedures the chi-square residualN= ∑ (L obsi − L i ) 2, 2 i=1(2)where L i obs and L i are, respectively, theobserved and modelled brightnesses atthe N observation epochs.Rotation parameters are easilyintroduced through rotation matricestransforming coordinates between theasteroid frame and a global frame suchas the ecliptic or equatorial one(Kaasalainen et al. 2002c; also cf. Fairbairn2003). For most asteroids these parametersare the direction of the spin axis and thesidereal rotation period. Some asteroidsare precessing, that is, their rotationalstates have not yet relaxed to the so-calledprincipal-axis rotation due to energyFigure 1. – Equatorial views of the light curvebasedmodels of asteroids 1580 Betulia (top)and 3908 Nyx bottom).dissipation in the tumbling asteroidmaterial. Such precession can also bedescribed mathematically and thecorresponding parameters can be includedin the coordinate transform (Kaasalainen2001). Light curve observations can alsoreveal binary asteroids revolving aroundeach other (Pravec et al. 1998, Mottola &Lahulla 2000).The direct problem is thus quitestraightforward via (1). The inverse problem,however, is notoriously difficult, and hasoften been thought unsolvable. Indeed,it was something of a surprise to find outthat, when merely natural and simpleconstraints are applied, the problem hasa well-defined solution. The path to thissolution is rather a winding one andinvolves a number of mathematical andphysical considerations I will not discusshere (Kaasalainen & Torppa 2001;Kaasalainen et al. 2002c). The main resultsare that the rotation parameters can bededuced very accurately, and the globalshape can be well inferred. This shapecan be thought of as the convex shapebest mimicking the silhouette of the bodyin all viewing directions. Detailedtopographic/nonconvex features canFigure 2. – Two light curves of 1580 Betulia.Asterisks are the observed intensity points (inrelative units), and the dashed line is the modelfit, plotted against the rotational phase (indegrees). The polar angles of the Earth andthe Sun, as seen from the asteroid, are θ andθ 0 , respectively. The solar phase angle is givenby α. Note the very rapid change of the lightcurve shape as the observing geometry changes,caused by the irregular shape and the highsolar phase angle.seldom be confirmed using disk-integratedphotometric data alone (D˘urech &Kaasalainen 2003). This is typical of anyinverse problem: some information isoften inevitably lost on the way, in thiscase due to the smoothing effect ofintegration over the disk. Our job is tomake sure we gather everything that theinformation source has to offer. The importantthing here is to have data from variousobserving geometries, and above all whenthe solar phase angle α = arccos(E · E 0 )isnot low, that is, the shadowing effectsrevealing the shape are prominent. Weshow examples of the models and lightcurves of two near-Earth asteroids(NEAs) 1580 Betulia and 3908 Nyx inFigures 1–3.There are some 10,000 recordedlight curves of several hundreds of objects(Lagerkvist et al. 2001), and the numbersare growing. We have so far built modelsof over eighty objects (e.g. Kaasalainen284JRASC December / décembre 2003

Figure 3. – Two light curves of 3908 Nyx,together with the model fits.et al. 2002a,b, 2003; Slivan et al. 2003;Torppa et al. 2003), and at least as manycan be analyzed in the near future withthe aid of well-planned observations.NEAs are especially rewarding targets.Due to the quickly changing observinggeometries, a comprehensive model of aNEA can often be constructed after anobservation span of only a few months.In addition to NEAs, there are numerousmain-belt asteroids (MBAs) for whichonly one or two more observationcampaigns are needed to compile a gooddata set.2.2 Complementary data: radar,interferometry, occultationsThere are other sources of informationthat are perhaps not as robust and easilyavailable as photometry, but have acomplementary character. Combiningeven a limited number of such data withphotometry can result in a more detailedsolution. We have recently started doingthis with radar and interferometricobservations and occultation timings. Inthe following I briefly list the basic modelsfor these sources to show that themathematical relationship between themodel parameters and the observablesis always quite straightforward. It is thebacktracking that is the hard part.Radar is a powerful tool for asteroidobservations (Ostro et al. 2002). A delay-Doppler experiment not only measuresthe intensity of the reflected radar signalas a function of the Doppler frequency(different surface points have differentradial velocities due to asteroid’s rotation);it also measures the intensity as a functionof (very accurately determined) time. Thisgives the radar depth coverage as parts ofthe body further away from the radarreflect the same signal back later. Now theobservable “coordinates” (d, D) (d for depthand D for apparent Doppler velocity inthe radial direction away from the observer)and the surface point r = (x, y, z) in theasteroid’s own coordinate system arerelated byd =− ( xcos+ ysin )cos−zsin,D= cos ( ycos−xsin ),(3)where ω is the angular speed of theasteroid’s rotation about its axis, δ is thesub-radar latitude, that is, the latitudeof the radar as seen from the asteroid,and ϕ is the sub-radar longitude. Theoften-shown radar “image” of anexperiment is a plot of the combinedobserved intensities of all visible surfacepatches in the (d, D)-plane, so it shouldnever be mistaken for a snapshot of thetarget. For one such plot, there are stillseveral surface patches that correspondto the same (d, D)-pixel. The “brightness”of one pixel is the integrated radar crosssection (echo strength) of these patches,computed just as in (1) (now µ = µ 0 andS ~ µ n ).If there are delay-Doppler experimentsfor several epochs, and the latitude δ isdifferent from zero, the many-to-one pixelmapping is different for different images,and one can use this to create a modelof the target (Ostro et al. 2002). In practice,this results in standard least-squaresoptimization. For asteroids not close tothe Earth, however, the echo power isusually not sufficient for depth resolution,so we get a Doppler-only signal (alsoknown as CW, continuous wave). Nowthe echo power for one frequency is givenFigure 4. – A test shape and its Doppler radarprofile (asterisks), together with the fits froma light curve+radar-based model (dashed line)and light curves-only model (dot-dash).by integrating over surface patchescorresponding to one D-bin. These dataare usually not sufficient for reliable objectmodelling by themselves. Since theirinformation is “orthogonal” to photometry,they can be employed to give additionalaccuracy to models based on light curveinversion. An example of this is shownin Figure 4. A contact-binary type asteroidshows the waist between its two mainparts in a Doppler profile, but lightcurvesseldom carry information on suchindentations unless they are very largeand are observed at very high solar phaseangles (D˘urech & Kaasalainen 2003).Interferometry is another majorremote sensing technique. It is based onthe fact that even though the target cannotbe resolved, its nonvanishing angular sizeinevitably disturbs the optical standardinterference pattern that would be obtainedfrom a pointlike source. The disturbanceshave a much larger angular width thanthe source. The disturbed pattern is aconvolution of the undisturbed one withthe plane-of-sky image of the target.Denoting the plane-of-sky distance alongthe scanning direction by x we have1P( x) = I( u, v) T ( x − ucos + vsin ) dudvL∫∫ ,(4)December/ décembre 2003 JRASC285

where we integrate over the plane-of-skyimage intensity I(u, v) of the target (u, vare the chosen plane-of-sky coordinates),T(x) is the standard interference patternstrength, and γ is the plane-of-sky tiltangle between x- and u-directions. Thefinal pattern P is normalized with thetarget’s total disk-integrated brightnessL=I(u,v)dudv. The model imagedistribution I(u,v) is directly given by theplane-of-sky projections of the surfacefacets and their brightnesses dL from (1),so the interferometric case is simply anextension of the photometric one, andthe inverse problem can be handledaccordingly. One cannot reconstruct animage from one scanning session, but wecan use all available data from severaldates and geometries to make a full model.We use, for example, the FineGuidance Sensor interferometry fromthe Hubble Space Telescope with twoorthogonal scanning directions (Hestrofferet al. 2002; Tanga et al. 2003). Interferometricdata are, of course, obtained much lessoften than photometric data, so againthey alone are not sufficient for modellingin practice, but they are a valuable additionto photometric information.Timings of stellar occultations byasteroids are gathered almost exclusivelyby amateur astronomers. These are ratherfragile and fortuitous events, but inprinciple contain snapshot profiles of thetarget if well observed. Here the directproblem is again easily expressed. For agiven occultation timing ∆t from someepoch, the proper observed quantities(coordinates of a “profile point”) can bewritten as( , ) = ˆ s ⋅( x+ ∆v∆t), ˆ s ⋅( x+∆v∆t) (5)where x is the observer’s position on theEarth in the sidereal equatorial frame,given by x= (Rcoscos , Rcossin , Rsin)(with R the local Earth radius, β thelatitude, and θ the local sidereal time),∆v denotes the differential space velocityv Earth – v asteroid , and the silhouette planeprojection unit vectors can be chosento beˆ s = ( −sincos , −sinsin ,cos ),ˆ s = (sin , −cos , 0),[ ](6)where α and δ are the right ascensionand declination of the occulting star. Thecorresponding projection point of a surfacepoint r of an asteroid model is simply( , ) (ˆ ˆmod mod= s⋅req, s⋅ req) + ( 0, 0),(7)where r eq is r transformed to the equatorialcoordinate system by the rotationparameters, and (ξ 0 , η 0 ) is some offset.The inverse problem consists of adjustingthe model r and rotation parameters suchthat the theoretical profile line coincideswith the observed profile points as wellas possible. Now even some large concaveformations are resolvable in principle,and we also get the size scale of the targetdirectly as with radar and interferometry.There are some other remote sensingsources as well, most notably thermalinfrared observations and polarimetry.The former is, again, closely related toordinary photometry, but in this case wealso have to invoke a thermal model toexplain the transfer of heat in the surfacematerial, which brings us to slightly lesswell-known practical physics. The sameapplies even more to polarimetry: modelsof the polarization states caused by thesurface material are as yet virtuallynonexistent.3. Amateur observations are importantA revolutionarily efficient practice inphotometry is the extensive (and intensive)use of small telescopes. Accurate CCDphotometry of targets brighter than aboutmagnitude 15 is quite feasible with relativelyinexpensive telescopes less than 40-cmin aperture. Even high-quality telescopesof only 20-cm or somewhat smaller arestill useful. This means that there are atleast hundreds of instruments in theworld equipped for the asteroid modellingproject. Most remarkably, many of theseare operated by dedicated and skilfulamateur astronomers. Best amateurs canroutinely make observations on a parwith small professional observatories atan automated level (or actually surpassthem — so far, only amateurs have beenable to deliver a desired light curveovernight with complete instrumentalreductions!). Amateur observations arethus just as important as professionalones — occultation timings or light curvedata from a 20-cm telescope are analyzedsimultaneously with those from the largeArecibo radio telescope or the HubbleSpace Telescope! It is also important tonote that getting good photometriccoverage for hundreds of asteroids takesthousands of hours of telescope time.This makes amateur observersindispensable: it would be physicallyimpossible to get enough observing timefrom professional telescopes for thisproject. What is more, this observingmode is extremely flexible andnonbureaucratic. Amateurs can alsoperform intensive observing campaignson a specific target — this is often usefulduring one apparition of a NEA (see, e.g.Koff et al. 2002). Two examples of verygood amateur observations of relativelybright MBAs are shown in Figure 5. Thedata are consistent and have very littlenoise even though they were obtainedwith a small telescope.A natural form of organization forasteroid light curve observers is a flexiblenetwork mainly communicating over theInternet. I list here a few hubs of this network;links and people cited on these sites forma natural guide for those interested in thesubject. An introduction to the project,an alert list of good asteroid targets,some publications, and other materialare presented on the Web pages of ourproject on inverse problems in astronomy(www.astro.helsinki.fi/~kaselain).Once the equipment is there, making actualscientific observations of an asteroid isquite straightforward after some practice.An excellent link containing plenty of adviceand other links is Brian Warner’s CALL(Collaborative Asteroid Lightcurve Link)site www.MinorPlanetObserver.com/astlc/default.htm. Another informativelink is Richard Kowalski’s ALPO (Associationof Lunar and Planetary Observers) asteroidobserving program site www.bitnik.com/mp/alpo/. Information on occultationtimings is given on the IOTA (InternationalOccultation Timing Association) pageswww.lunaroccultations.com/iota/asteroids/astrndx.htm.286JRASC December / décembre 2003

Figure 5. – Two light curves of 37 Fides and129 Antigone by R. Kowalski, obtained withan 18-cm Maksutov telescope and an SBIGST-7E CCD camera.The first stage of photometric asteroidobservations is to get the first few lightcurves of a target, enabling one to get thefirst estimate of its rotation period andperhaps some hints of its shape character.Rotation periods are already known forhundreds of asteroids, and it is possibleto draw important statistical inferencesfrom such a set (Pravec et al. 2002).The second stage is to get more lightcurves at new apparitions, thus providinginformation at new viewing/illuminationgeometries. An efficient way of gettingthe most of one asteroid apparition is toobtain two light curves at the largestuseful solar phase angles (to get ameaningful part of the period covered;more than one night is good for this), andone at a smaller phase just to get as longa stretch as possible. The high phaseangles are important for reaching maximalshadowing effects (and light-scatteringbehaviour different from the simple neargeometricmode near opposition). A denselight curve sequence contains a wealthof information and helps to rule out errors.Several tens of points per rotation periodare the optimum, so an automaticobservation mode is necessary. A goodpractice is to eliminate potentialsystematical errors by observing on twoadjacent or at least nearby nights,particularly if the rotation period is notshort enough for overlapping rotationalphases during one night. In this way onecan be sure that possible features in thelight curve are really repeated and notartificial.Finally, sending the observations tobe analyzed is very easy. The data can besent by email (in a flexible format) to meor to Brian Warner (or to anyone else whois gathering and forwarding observationsto us for analysis); we are also in theprocess of building an automated Internetservice for this purpose. The observeralways gets author credit in the paperwhere the data are published.4. Conclusionsand encouragementSolar system bodies are fascinating alreadyfrom the point of view of data acquisitionas few astrophysical targets offer such awide repertoire of data sources. We livein the golden era of planetary research,and particularly for small solar systembodies this era has just begun. Amateurobservers have now a great chance toparticipate in solar system explorationand help to make the asteroid populationas well known as the larger planets.While “what do they look like?” isthe natural prime incentive for acquiringphotometric data, the follow-up question“why do they look like that?” is just asimportant. When we have a large numberof asteroid shape and spin models at ourdisposal, we can draw important statisticalinferences on the origins and evolutionof this population. To mention just oneexample, Slivan et al. (2003) used thesemethods to investigate the curiousclustering of the spin states of small(20–40 km) members in the Koronisasteroid family. Recent results (Vokrouhlickyet al. 2003) suggest that such clusteringcould generally take place in this sizeregion in the outer asteroid main belt atlow inclinations. If evidence for this isfound in the overall asteroid population,we will have important new clues todynamical evolution particularly due tothe so-called YORP (Yarkovsky-O’Keefe-Radzievskii-Paddack) thermal radiationpressure effect.ReferencesD˘urech, J., & Kaasalainen, M. 2003, A&A,404, 709Fairbairn, M. 2003, JRASC, 97, 92Hestroffer, D., Tanga, P., Cellino, A.,Guglielmetti, F., Lattanzi, M., DiMartino, M., Zappalà, V., & Berthier,J. 2002, A&A, 391, 1123Kaasalainen, M. 2001, A&A, 376, 302Kaasalainen, M., & Torppa, J. 2001, Icarus,153, 24Kaasalainen, M., Torppa, J., & Piironen,J. 2002a, A&A, 383, L19Kaasalainen, M., Torppa, J., & Piironen,J. 2002b, Icarus 159, 369Kaasalainen, M., Mottola, S., & Fulchignoni,M. 2002c, in Asteroids III, eds. W.Bottke, R. Binzel, P. Paolicchi, & A.Cellino (University of Arizona Press:Tucson), 139Kaasalainen, M., & 16 colleagues 2003,A&A, 405, L29Koff, R.A., Pravec, P., S˘arounová, L.,Kusnirak, P., Brincat, S., Goretti, V.,Sposetti, S., Stephens, R., & Warner,B. 2002, Minor Planet Bulletin, 29,51Lagerkvist, C.-I., Piironen, J. & Erikson,A. 2001, Asteroid PhotometricCatalogue, Fifth update (UppsalaUniversity Press: Uppsala)Mottola, S., & Lahulla, F. 2000, Icarus 146,556Ostro, S., Hudson, S., Benner, L., Giorgini,J., Magri, C., Margot, J.-L., & Nolan,M. 2002, in Asteroids III, eds. W.Bottke, R. Binzel, P. Paolicchi, & A.Cellino (University of Arizona Press:Tucson), 151Pravec, P., Wolf, M., & Sarounova, L. 1998,Icarus 133, 79Pravec, P., Harris, A.W., & Michalowski,T. 2002, in Asteroids III, eds. W.Bottke, R. Binzel, P. Paolicchi, & A.Cellino (University of Arizona Press:Tucson), 113Slivan, S., Binzel, R., Crespo da Silva, L.,Kaasalainen, M., Lyndaker, M., &Krco, M. 2003, Icarus, 162, 285December/ décembre 2003 JRASC287

Tanga, P., Hestroffer, D., Cellino, A., Lattanzi,M., Di Martino, M., & Zappalà, V.2003, A&A, 401, 733Thomas, P.C., Veverka, J., Simonelli, D.,Helfenstein, P., Carcich, B., Belton,M.J.S., Davies, M.E., & Chapman, C.1994, Icarus, 107Thomas, P.C., Belton, M.J.S., Carcich, B.,Chapman, C., Davies, M.E., Sullivan,R., & Veverka J. 1996, Icarus 120, 20Torppa, J., Kaasalainen, M., Michalowski,T., Kwiatkowski, T., Kryszczynska,A., Denchev, P. & Kowalski, R. 2003,Icarus, 164, 346Vokrouhlicky, D., Nesvorny, D., & Bottke,W. 2003, Nature, 425, 147Zuber, M.T. et al. 2000, Science, 289, 2097Mikko Kaasalainen earned a D.Phil. intheoretical physics at Oxford University. Aftera grand tour of European institutes as apostdoc, he returned to Helsinki University,got married, built a house, and is now a seniorresearcher at the Rolf Nevanlinna Institutefor mathematics. He still hopes to actuallylook at something through a telescope oneof these days.Orbital OdditiesMartian Motion IV: The Zeus Effectby Bruce McCurdy, Edmonton Centre (bmccurdy@telusplanet.net)When the moon is in the seventh houseand Jupiter aligns with MarsThen peace will guide the planetsand love will steer the starsThis is the dawning of the Age of Aquarius— James Rado and Gerome Ragni,“Aquarius”(from the Broadway musical Hair)Another sequel?” theimaginary reader may be“What!?saying upon seeing thattitle. “Isn’t this Mars thing getting kindof old?”Welcome back to Orbital Oddities,imaginary readers, where the old, thenew, the past, present, and future all getballed up to the extent that I frequentlyam confused as to which tense I’m in. Ifin the process, I forget how tense I am,it will have been worth the diversion.Over the summer as Marsapproached, I fell into an e-conversationwith the man I consider the Orbital Oracle,Jean Meeus. The Belgian Calculator hada 27-year head start on me, and at 75 thisamazing man continues to widen the gapwith his prodigious mathematical skills.But I wrongly assumed that he knewsomething about all things orbital, andwas surprised when he admitted to me,“I have not studied the effect of Jupiterin the perihelion distances of Mars.”(Meeus 2003a) This proves if nothing elsethat the number of problems is trulyinfinite.While a very good first-orderapproximation of a planet’s orbit can bemade considering only the Sun, the planetsdo influence each other to a tiny degree.Nowhere near as much as the astrologerswould have you believe, but a measurableamount. Collectively these are rathermysteriously referred to as secularvariations. I figure I’m a secular kind ofguy, why not have a go?In Parts I and III of the MartianMotion series, I concluded, withoutquantitative analysis, that the positionof Jupiter influences Earth-Mars distances.By evaluating its influence on Mars’perihelion, I am now closer to quantifying“The Jupiter Effect” (to invoke the titleof a rather unfortunate book thatspectacularly failed to bridge the everwideninggulf between astronomy andastrology). Let’s call it the “Zeus Effect”instead.According to Meeus (1983-95), Marsreaches perihelion every 687 days at slightlydifferent distances from the Sun. In the61 years (1960-2020) listed in the table,these range from 1.38115 to 1.38156 AU,a seemingly tiny difference of ~0.0004 AUthat nonetheless amounts to some 60,000km. I note perihelia of < 1.38130 AU occur(only) in the following years: 1967, 1979-81, 1992, 2003, and 2014-16. Surely this~12-year periodicity suggests acommensurate relationship with Jupiterand its 11.86-year orbit. A good way totest this is to lay out the data in a Meeusstylepanorama, shown as Table 1.There seems to be sufficient evidenceto claim a periodicity with a primaryminimum (extreme close perihelion) of~1.3812 AU at 12-year intervals clusteredroughly under column 1967, and asecondary minimum of ~1.38135 undercolumn 1962. In the first instance, as seenfrom Mars, Jupiter is in conjunction withthe Sun around the time of perihelion,in the second near opposition. Distantperihelia ~1.3815 occur when the two arenear quadrature. Figures along eachdiagonal show a consistent rise and fallas they slice through the implied peaksand valleys. Last-digit “noise” in the datacan be attributed to the influences ofother planets, primarily Earth.288JRASC December / décembre 2003

Table 1. – There are roughly 6.3 revolutions of Mars for every one of Jupiter. The Red Planetreaches perihelion around 336° heliocentric longitude at each of the data points shown, whichoccur from left to right at intervals of 1.88 years. The date of the first event of each “column” isshown at top; of each row, at left. The perihelion distances, showing just the last two digits(1.381xx AU; e.g. 1967 = 1.38123 AU), are laid out as a panorama on this scale of 6.3:1. Impliedvertical columns occur at roughly 12-year intervals and correspond to Jupiter at a particularheliocentric longitude (shown at bottom). The table indicates that the closest perihelia are clusteredwhen Jupiter is near celestial longitude 156°, with a secondary minimum around 336°.This seems analogous to the Moon’sperigee cycle, which is essentially a tidalrelationship. The closest perigees occurwhen the Moon is at syzygy, either newor full, but the most extreme perigees alloccur at Full Moon. The geometry of Earthand Sun on the same side is for somereason, slightly better than at 180 degreesin pulling the Moon particularly close.In the case of Mars, close perihelia occurwith Jupiter in opposition, closer oneswhen it’s in conjunction, poor ones whenJupiter and the Sun are working at crosspurposes.(Call them “spring” and “neap”perihelia!) It was high tide with a vengeanceon August 30, 2003, when the Sun, Jupiter,Earth, and even Venus were all in near alignmentto one side of Mars. (See Figure 1).A similar panorama of Mars’ aphelia(Table 2) reveals a more subtle pattern.In this case there appears to be only oneminimum under column 1963, and onemaximum, centred roughly under column1968. I suspect in the latter case, thatthere are actually two maxima balancedon the shoulders of a very shallowsecondary minimum, in a manner roughlyanalogous to Algol’s light curve; there areinsufficient data to fully reveal this. Thediagonals aren’t quite so pleasinglyconsistent, but the pattern stronglyclose perihelion, as was that of 2003,which was almost certainly the closestsince many millennia. The orbitalcircumstances of Earth-Mars were notquite as favourable as 1924, except Marswas particularly close to the Sun, andtherefore to Earth in inferior conjunction,largely due to the influence of Jupiter insuperior conjunction. In essence Jupiterwas pushing the Sun away from thebarycentre of the solar system in thedirection of Mars, with slightly moreinfluence than it was pushing Mars itself.To paraphrase Meeus (2003b), thegravitational effect of Jupiter on Mars isof the “second order”: what counts is notthe direct attraction of Jupiter on Mars,but the difference between the attractionsJupiter-Sun and Jupiter-Mars.Of course, these gravitationalrelationships don’t happen in a vacuum(so to speak). A related question is howmuch Earth’s orbit is itself deformed closerto the Sun for the same reasons. This ismore difficult to determine: ephemeridesTable 2. – Mars’ aphelion distances from 1961-2019, showing the last three digits (1.66xxx AU). TheRed Planet is near longitude 156° at each data point. The shallowest aphelia are clustered when Jupiteris around 336°, once again indicating that Jupiter in conjunction with the Sun has the effect of bringingMars slightly closer. Exactly half of the 32 aphelia on this period have values of 1.66600 or higher, andall 16 are located on the right half of the panorama; the 16 events of 1.66599 or below are all on the left.A comparison of the top and bottom rows (1961 and 2008) reveals that all values have increased by0.00004-0.00008 AU, due to Mars’ increasing eccentricity. Note that the two deepest aphelia of the entireperiod occur consecutively in 2002 and 2004, indicating that the current “wobble” of Mars‚ evolving orbitis particularly eccentric, achieving modern records for distance from the Sun at both extremes of the orbit.Figure 1. – An overview of the solar systemas Mars reached perihelion on August 30,2003 shows the favourable alignment of threeother planets with the Sun.suggests a periodicity of about twelveyears. As is the case with the Moon, therange of aphelion values is significantlylower than that for perihelion.I noted in Martian Motion I (McCurdy2003), the unusual slope and asymmetricflattish peak of the current 79-year seriesof close approaches of Mars to Earth.Let’s look at it again in the context ofJupiter’s position in Table 3.The 1766 figure of 1.38148 AU was,in the context of its times, an extremelyare for Earth itself, which wobbles ±0.00003 AU to either side of the Earth-Moon barycentre. The variations introducedby lunar phases can advance or delay thedate of perihelion by up to two days, nearlyoverwhelming the subtle residuals of thesecular variations (Meeus 1997). Thatsaid, surely it’s no coincidence that Earth’sclosest perihelia in the 41-year period1980-2020 (the only three < 0.983250 AU)occur in early January of 1985, 1996, and2020; and the two shallowest aphelia (

Table 3Year Mars-Earth Mars- Sun Jupiter’s “Adjusted” “Adjusted”(AU) Perihelion Longitude Perihelion Mars-Earth1766 0.37326 1.38148 152° (+176°) 1.38178 0.373561845 0.37302 1.38167 29° (+53°) 1.38167 0.373021924 0.37285 1.38159 261° (-75°) 1.38159 0.372852003 0.37272 1.38115 150° (+174°) 1.38145 0.373022082 0.37356 1.38131 25° (+49°) 1.38131 0.37356Table 3. – The current 79-year series of close Mars-Earth approaches, with perihelion calculationsgraciously provided by Jean Meeus. Earth is in virtually the same location in all five cases,eliminating the primary source of “noise” in the data and further isolating the “Zeus Effect.”Bracketed figures after Jupiter’s longitude show its relationship to Mars: In the two cases whereJupiter is in conjunction nearly 180°, Mars is unusually close to Earth, presumably because it ishaving unusually close perihelia. Applying our previous findings that Mars is ~0.0003 AU closerto the Sun under these circumstances, we can “correct” for this variable by adding in this amountto the perihelia of 1766 and 2003. This yields the near-regular slope of ~0.00015 AU/Cy in the“adjusted perihelion” column, which can be attributed to Mars’ increasing eccentricity. A similaradjustment for the Mars-Earth distance shows a very regular curve in the series, supporting theauthor’s original supposition that this series “should” have peaked in 1924, and that only theposition of Jupiter led to its record-setting status in 2003.1.016660 AU) occur in July 1990 and 2001.As we found with Mars, without exceptioneach of these five “extreme” events occurswithin a couple of weeks of a conjunctionof Jupiter with the Sun.Even with the influence of the Moon,the range of variation of Earth’s periheliondistance is just 0.00012 AU, only some30% that of Mars. One can conclude thedifference between the attractions ofJupiter-Earth and Jupiter-Mars when theKing of Planets is ~ 180° from both, wouldhave the net effect of drawing Mars slightlycloser to Earth as well as to the Sun, aswe have witnessed in 2003.We know that the Earth-Mars closestapproach record will be broken in 2287,however, the Martian perihelion recordwill surely fall much sooner than that.Mars achieves perihelion on each revolutionof the Sun, not just once every 79 yearsor whatever, and the gradual increase inits eccentricity makes the near continualapproach of perihelion inevitable. Whatis moderating this, in that a new recordis not set each orbit, is tiny differencesin the “waves” due (primarily) to Jupiter’schanging aspect at each instance.I checked out future Mars periheliabeyond 2020 on Guide 7.0, which I firstdetermined to be extremely accurate toMeeus’ table. Considering the factors inthis order of importance: 1) ongoingincrease in Mars’ eccentricity; 2) positionof Jupiter; 3) position of Earth, and notingthe 47:25:4 near resonance among thethree, I figured 2050 as a likely date for anew record.Aug. 30, 2003 1.38115 (Jupiter 150°, Earth 337°)Dec. 12, 2014 1.38121 (Jupiter 133°, Earth 81°)Oct. 29, 2016 1.38124 (Jupiter 186°, Earth 36°)Feb. 11, 2028 1.38116 (Jupiter 170°, Earth 142°)May 26, 2039 1.38111 (Jupiter 154°, Earth 246°)Sept. 7, 2050 1.38111 (Jupiter 138°, Earth 345°)It turns out that Jupiter is particularlywell aligned in 2039 some 182° fromMars’ perihelion, so the 2003 perihelionrecord will be broken then. The newmark will be equaled, or very nearly so,in 2050 when Jupiter’s position issomewhat less favourable but Earth’smuch more so.In the course of our correspondence,Meeus (2003c) stated: “It was amusingto read what your wife said about myTables (“how can you read that? Nothingthan numbers!”). Actually, there is muchpoetry in those tables, if you can lookFigure 2. “The Age of Aquarius” as seen fromJupiter. On August 20, 2003 (shown), Venus,Earth, and Mars all clustered within 20arcminutes of the Sun, against the backdropof the constellation of Aquarius. Uranus canbe seen only 1.5° away. While only 3.7° distantand also in Aquarius, Mercury was nearmaximum western elongation, and Saturn toowas well out of alignment.at them carefully. Certainly astronomicaltables are on a higher level than suchthings as telephone books...!”If you’ll forgive a philosophicalmoment, the anarchy of true randomness(numbers in the phone book) is asuninteresting as the fascism of absolutecertainty (e.g. 1.0000000...). The realUniverse is a delicate, indeed poetic,balance between order and chaos, theinterface of which can be best appreciatedfrom the water’s edge. The waves breakingon the shore are superficially the samebut when examined closely each is unique.Is there a pattern? I try to pick out thoselittle ripples at the extreme edges of thetables and see if I can discern the logicbehind them. And the little moments of“discovery,” even as they inevitably proveto not be truly original, are nonethelessprofound.Segue to the trivial: in 2003 Jupiterdid align with Mars, with the latterappearing in Aquarius. Just because I’ma curious kind of guy, I looked up theastrological position of the Moon on thedate of Mars’ closest approach to Earthand Sun, and found it to be - to the bestof my limited understanding and interest- in the sixth and seventh houses,respectively.But I’m still waiting for that peaceand love thing to kick in. Until it does,consider my belief in astrologicalprophecies to be on indefinite hold.290JRASC December / décembre 2003

AcknowledgementThe writer gratefully acknowledges theassistance of Jean Meeus (RASC HonoraryMember), to whom this article is dedicated.ReferencesMcCurdy, B. 2003, JRASC, 97, 98Meeus, J. 1983-95, Astronomical Tablesof the Sun, Moon and Planets (2ed:Willmann-Bell Inc.: Richmond), 30Meeus, J. 1997, Mathematical AstronomyMorsels, (Willmann-Bell Inc.:Richmond), 169Meeus, J. 2003a, 2003b, 2003c, privatecommunicationsBruce McCurdy is active in astronomyeducation with RASC Edmonton Centre,Odyssium, and Sky Scan Science AwarenessProject. He currently serves National Councilas Astronomy Day Coordinator. He is perverselydelighted that his only child was born underthe “sign” of Ophiuchus.Observation of the 1761 Transit of Venusfrom St. John’s, Newfoundlandby Frederick R. Smith, St. John’s Centre ( frsmith@morgan.ucs.mun.ca)On May 9, 1761 the province–sloopMassachusetts left Boston and in13 days arrived in St. John’s,Newfoundland. The passengers were JohnWinthrop, Hollisian Professor ofMathematics and Philosophy, and two ofhis students from Harvard College. Theywere headed to St. John’s to observe thetransit of Venus on what appears to havebeen the first American scientificexpedition. This was one of a number ofworld-wide expeditions attempting touse Edmond Halley’s method to measurethe solar parallax and thereby determinethe length of the astronomical unit.While institutions throughout Europehad a long history of scientific research,few people in North America had verymuch training in astronomy andmathematics. However there was oneoutstanding scientist at Harvard College,John Winthrop. Winthrop had publishedon comets, sunspots, and otherastronomical phenomena and had beenwell aware of the up-coming transit ofVenus and also that St. John’s,Newfoundland would be the mostconvenient place in North America wherethe transit could be observed; the coastof Labrador was considered out of thequestion. Unfortunately, less than an hourof the transit could be observed from St.John’s since the transit started well beforesunrise in Newfoundland (the 2004 transitwill present a similar situation).Winthrop’s colleagues conveyed aletter to Francis Bernard, Governor ofthe Province of Massachusetts, requestingthat the legislature fund a trip to St. John’s,Newfoundland to observe and measurethe transit. The governor supported theexpedition and had little trouble inconvincing the legislature of the importanceof the event. The legislature assigned theprovince-sloop Massachusetts, underCaptain Thomas Saunders, to takeWinthrop and his students to St. John’s.The administrators of Harvard Collegealso wanted to contribute to the expeditionand gave Winthrop permission to takeany of the college instruments, as longas they were insured against loss or damage.To quote Winthrop:“The Reverend the Preƒident andFellows of Harvard College, in orderto promote ƒo laudable an undertaking,granted their Apparatus of aƒtronomicalinƒtruments, to be imploy’d in thisaffair. Accordingly, I carried an excellentPendulum clock; one of Hadley’sOctants with Nonius diviƒions, andfitted in a new manner to obƒerve onƒhore as well at ƒea; a refractingtelescope with croƒs wires at half rightangles for taking differences of RightAƒcenfion and Declination; and acurious reflecting teleƒcope, adjuƒtedwith ƒpirit-levels at right angles toeach other, and having horizontal andvertical wires for taking correƒpondentaltitudes; or differences of altitudesand azimuths.”The sloop took 13 days to travel fromBoston to St. John’s. and upon arrivalWinthrop and his two students were givena good reception.“The town of St. John’s being boundedwith high mountains towards the Sunriƒing,ƒo that no houƒe in it wouldanƒwer our need, we were obliged toƒeek further; and, after a fatiguingand fruitleƒs attempt or two, fix’d onan eminence at ƒome diƒtance.”It took several days to get all of theirequipment to the observing site wherethey then had to set up several tents anddrive posts securely into the ground forthe pendulum clock and other equipment.Before the transit they had lots of timeto check out the equipment and adjustthe clock and be assaulted by“ƒwarms of inƒects, that were inpoƒseƒsion of the hill...”December/ décembre 2003 JRASC291

On the morning of June 6, 1761 it was“ƒerene and calm.” The sun rose behinda cloud but soon became visible, and thetransit was observed and measured.Where did Winthrop make hisobservations of the transit of Venus?The local gentlemen who turned out towatch the transit named the place “VenusHill” in honor of the occasion, but thatname has never turned up in any officialdocuments or maps.When Simon Newcomb wasdocumenting the sites of transitobservations, he wrote the St. John’sHarbour Master and was told Winthropmust have observed from the FortTownshend area (Newcomb 1891). Thefort was actually built a couple of yearsafter Winthrop’s visit.In his journal Winthrop gives thecoordinates of his place of observation.He and his assistants had measured thelatitude many times and the value 47°32´ recorded in his journal is probablyfairly accurate. It is interesting to notethat in the Philosophical Transactionsthe latitude is given as 47° 31´. Longitudedetermination is another matter. Thisperiod was before the development ofreliable chronometers, and there were nosolar or lunar eclipses while he was in St.John’s, and because of the weather he wasnot able to observe either of the twoeclipses of Jupiter’s moons that occurredduring his visit. Having no way to measurelongitude, he quoted the value listed inthe literature, a point out in the AtlanticOcean and of no use in locating hisobservation site.What do we look for in trying tolocate Winthrop’s observing site?1. I used his latitude line as quoted inhis journal and explored an area onenautical mile north and south of thisline.2. On June 6, 1761 the azimuth of sunrisefrom St. John’s was approximately 54degrees true. One obviously must beable to look in that direction andhave a clear view of the horizon.3. The ground must be suitable fordriving heavy posts securely in place.4. The high point must be such that itwould take several days to get all theequipment to the site but be withinwalking distance (there were horsesin St. John’s in those days).5. It must be an area where one wouldexpect biting flies in large numbers.ObservationsI walked and drove over all of St. John’sand surroundings with compass, map,and GPS in hand and noted on the mapany area where the horizon could havebeen seen at an azimuth of 54 degreestrue.The easiest site to deal with was FortTownshend. Newcomb would have beenable to eliminate it immediately if adequatetopographic maps had been available.Even a quick drive by will show that, atthe azimuth of the 1761 sunrise, thehorizon is blocked from view by the WhiteHills and Signal Hill. However there is abeautiful view of the horizon through St.John’s narrows, and the harbour mastermust have taken for granted that the Sunwould have been visible in that direction.Anyone with even a casual knowledgeof St. John’s would assume that the obviousplace to view any sunrise would be SignalHill. However Signal Hill was well knownand named, and this would have beenknown by the local residents in 1761. Itis also well north of Winthrop’s latitudeline.The next most obvious candidatefor an observing site would be the SouthSide Hills, also known as the South Hillsduring this period. The areas on the hilltops suitable for observing sunrise aretoo far north, and once again the localswould have known the name.When plotted on a modern daytopographic map, Winthrop’s quotedlatitude line runs straight through thehighest point of Kenmount Hill, an“eminence at some distance” from thecentre of the 1761 town and on the southwestperiphery of the present day city.Support for Kenmount HillAll parts of St. John’s are near the AtlanticOcean, but it is surprising that there areso few areas where it is possible to get aclear view of the horizon and even fewerin a particular azimuth.Kenmount Hill is one of the highesthills in the area, giving excellent visibilityof the ocean horizon in the azimuth ofsunrise in June 1761. The ground is suitablefor driving in poles for the clocks andtelescopes, and there are “lots” of bitingflies there during June.In the 21st century Kenmount Hillis known by St. John’s residents as a hillcovered by a coniferous forest andcommunications towers. However asHead (1976) and others have pointed out,the early residents needed wood for fuel,house building, ship repair, and structuresfor drying fish (fish flakes), and by the17th century the land was cleared of treesfor miles around the town. In additionroads extended in all directions from St.John’s (Mannion 2002), including overand around Kenmount Hill. Evenphotographs taken of the St. John’s areain the late 19th and early 20th centuriesshow few trees, and most of the spruceand fir on the hill are growth from thelast quarter of the 20th century.St. John’s has a history of beinginvaded by land forces, and in fact thetown was captured by the French the yearafter Winthrop’s visit and recaptured bythe English in the last battle of the SevenYears War (the Battle of Signal Hill). Sothere would naturally have been somemilitary interest in Kenmount Hill, andthis is supported by the remains of a trailknown, in old deeds, as Soldier’s Path,and near which a former resident of thearea (Sandland) had recovered 18th centurycoinage.Therefore, in the mid-18th centuryit would have been fairly easy for Winthropand his assistants to walk along therelatively low sloping hills, known in thosedays as “the Barrens,” on a route fromthe centre of the town to Kenmount Hill,292JRASC December / décembre 2003

perhaps using horses to carry theequipment. It would also have been easyfor the residents to reach the hill to watchthe astronomer at work.ConclusionBased on the evidence given above, I concludethat John Winthrop and his studentsobserved the 1761 Transit of Venus fromKenmount Hill, St. John’s.ReferencesHead, C.G. 1976, Eighteenth CenturyNewfoundland: A Geographer’sPerspective, (Carleton UniversityPress: Ottawa)Hindle, B. 1956, The Pursuit of Sciencein Revolutionary America 1735–1786,(University of North Carolina Press:Chapel Hill)Mannion, J.J. 2002, Department ofGeography, Memorial University ofNewfoundland, private communicationMannion, J.J., ed. 1977, The Peopling ofNewfoundland, Essays in HistoricalGeography, (University of TorontoPress: Toronto)Newcomb, S. 1891, Discussion ofObservations of the Transits of Venusin 1761 and 1769, AstronomicalPapers prepared for the AmericanEphemeris and Nautical Almanac,Vol. 2, No. 5Prowse, D.W. 1895, A History ofNewfoundland from the English,Colonial and Foreign RecordsSandland, T., private communicationWinthrop, J. 1761, Relation of a Voyagefrom Boston to Newfoundland forthe Observation of the Transit ofVenus June 6, 1761, Boston N.E.Winthrop, J. 1769, Royal Society of London,Philosophical Transactions (12)1763–1769AcknowledgementThis project would not have been possiblewithout the assistance of many people.Mr. Garry Dymond gave much valuableadvice and located many maps for theauthor. Thanks for many conversationsto historical geographers Drs. John Mannion,Alan MacPherson, and Joyce MacPhersonof Memorial University of Newfoundland(MUN) Department of Geography, to Dr.Alberta Wood and her staff of the MUNMap Library, the staff of MUN QEII Libraryand Centre for Newfoundland Studies,staff of the Public Archives of Newfoundlandand Labrador (PANL), and many peoplein the MUN departments of English, history,and geography. Thanks also to Mr. PeterBroughton for many stimulating emailconversations and his work with the RASCHistorical Committee to have the site ofthe 1761 transit observation marked bythe Canadian Historic Sites and MonumentsBoard as suggested by the InternationalAstronomical Union.Frederick R. Smith is a member of the RASCSt. John’s Centre. He teaches introductoryastronomy and astrophysics at MemorialUniversity of Newfoundland in St. John’s.Astrocrypticby Curt Nason, Moncton CentreHere are the answers to last issue’s puzzleDecember/ décembre 2003 JRASC293

Edmonton’s Amazing Marzathon 2003by Sherrilyn Jahrig, Edmonton Centre (sj_starskip@hotmail.com)Edmonton Centre’s Mars-watchbegan by mid-August whenObservatory assistants began stayinglate to watch Mars rise over the CoronationPark tree line. The smoke haze from themany fires ravaging the western provincesstill permitted the South Polar Cap toinspire exclamations from the guests.The first ripples of excitement andintimations of big crowds for the eventwere evident as the phone on deck beganringing constantly with questions aboutthe “big orange light in the south thatmoves around” or “how do I tell thedifference between Mars and the Moon?”The newspaper and screen-sized imageswere going to be hard to beat with the“skin-of-your-eye” telescopic view. Manypeople came out mid-afternoon demandingto see Mars and had to be content withan eyeful of daytime stars.The Observatory and RASC members’telescopes set up in the field gave a fullspectrum of Mars views, interpreted asa “little white dot” or a “Big Red Ball,”depending on your inner imaging system!One interpretation of the amazing andmostly accurate Edmonton media coveragewas that our telescopes were going togive whoppingly huge views of Mars thatwere bigger than your face. The real treatscame in assorted sizes, from the donationof mini-Mars Bars® to the big dome ofclear sky that accompanied most of ourtwelve official viewing nights. After a yearof clouded-out events, it was a relief tosay to the crowd, “You came on an excellentviewing night!” Features such as the S.P.Cap, Syrtis Major, Solis Lacus, HellasBasin, and even Phobos were visible. Thecomputer on deck was a great aid. WithMars Previewer set up and coupled withStarry Night Pro, we could show thingsto the bottleneck crowd at the door.Features of Mars and some short clipswith Carl Sagan and even War of theWorlds were popular. The new RASCdisplay board had a “Hiker’s Guide toMars” map and some prime Global Surveyorshots. These were the nights when wewere at our best: busy, taking pride in ourequipment and knowledge, running notonly on our own enthusiasm but that ofnew observers. Overall, the crowds werevery appreciative, and many returned foranother sampling of sky through themonth of September.And what crowds...! On Friday, August29, we hit the peak with several thousandpeople in a serpentine line from thetelescopes, through the parking lot, rightout to 142nd St. The following night, Brianfrom the Odyssium came up with a moreefficient crowd design that used thelooping sidewalks to more advantage.This enabled some of our impromptu SkyWalk presenters to reach more peoplewith their informative talks and the aidof the great green laser pointer. Insidethe Odyssium, Frank Florian gave extra“Sky at Night” live shows, up to threeconsecutive presentations, highlightingMars. Sometimes it was very difficult topersuade the public that some of thetelescopes in the field gave equal viewsand had shorter line-ups. Those whochose to believe had a variety of experiencedsky-guides and good equipment to choosefrom. On some nights these field lineswere so magnetic that they were half anhour long, still better than the three- tofour-hour Observatory line-up. At ourpeak on Friday night we wrapped thingsup with a nice image of Saturn in theeast...at 4:30 a.m.Several Odyssium staff donated theirtime as did the dedicated RASC volunteers.Each night there was anywhere from ahandful to over twenty volunteers. Onenight Ardith Edwards, the OdyssiumVolunteer Coordinator, handled the coffeeand hot chocolate sales with Chris, thereceptionist. Chris’ daughter Stacey tookher glowing angel wand and handed outplanet cards and chocolate to the kids inline. Whenever possible, after midnightwe would find families with small childrenand the elderly or handicapped guests tobring past the line-up and in the back ofthe Observatory. I have to admit thatsome nights we were overwhelmed bythe crowd/volunteer ratio, couldn’t quitelive up to our best-laid plans and had togo with Plan B. To quote Patti Jeske, whomust be personally responsible forrecruiting hundreds of new Observatoryfans, “We’ll stay open until the last visitorhas seen Mars, or until the Sun rises,whichever comes first.” The greatest heroeswere those who topped off “giving theirbest” with keeping their humour intact.Mars tips its S.P. Cap to you!One of my favourite nights was theclose approach on Tuesday, August 26-27. We had some cloud cover but still hada line-up of a few hundred. An artilleryof telescopes all centred to snipe Marsstood at attention along with a deck ofexpectant people. When it finally blazedthrough in all its horizon-distorted glory,the crowd went “OOOooooooooo...!!!” andthen a long “Awwwwwwww...” as it duckedimmediately into the cloud bank again.This repeated many times and the crowdbegan to exaggerate the Oos and Aws.Later we joked among ourselves aboutthe best public view of Mars. Putting theplanet out of focus (never deliberately ofcourse...) brought some satisfyingcomments: “Wow, it looks like bacteria,there is life on Mars; It’s huge and I thinkit’s on fire; I can see yellow and blue stuffin the atmosphere...” Kevin Jeske andBruce McCurdy stayed until the wee hoursto glimpse the actual closest approachand were blessed by a poignant cloudbreak. The following night it actuallyrained. I shut myself in the Observatory294JRASC December / décembre 2003

and answered chain-ringing phone-callsabout Mars, shouting answers above thedin of downpour on the metal roof. LarryWood helped me with a roof leak, and aswe walked through the rain to the parkinglot, a teenage girl, one of the many soakedvisitors that night, ran from her car askingif she could still view Mars.Early in the Mars-watch I realizedwe needed a little entertainment nearthe line-weary entrance wall to theObservatory. Past-president RichardVanderberg with his patient, informedexplanations and on-going humour wasa big help. I also placed a big whiteboardnear the door with a red lamp and somecoloured markers. Each night the boardwas filled with a multitude of new Martians.Artists of all ages tried their hand atconjuring other life in the universe. Nocreation was as strange and wonderfulas the people, tigers, dolphins, and toucansthat already populate our Earth. One nightwe even had a theatrical troupe of “greenlightdancers” on the little green hill northof the deck; I had coincidentally met themas I went into my “day-job” at theObservatory that afternoon.During the last few nights with ourhumour wearing a little thinner, I foundmyself pointing out the Martian featureBeer Crater on the computer, or at leastthe Near Beer Crater, as you really had tozoom-in to find it. No liquid there. Maybesome atmospheric ice? There was notmuch of this type of indulgence duringour Mars-watch...after all, what was openand respectable in the pre-dawn hours?We took turns running the rails behindthe Observatory with hot-chocolate andTiM57s (donuts). On our more desperatenights a person could feel like her feetwere duct-taped to the concrete for manyhours. Every morning in kitchens acrossEdmonton, Marzathoners did theMarswalk, a very slow gliding motionwith bent knee, with care taken not toshatter calluses. When the long nightswere done, we all felt we had truly donatedour soles to science.So it’s over, but it was everything wehad been rehearsing for: a historical event,great weather, no major dust storm onMars, excellent media coverage, dedicatedand energetic RASC and Odyssiumvolunteers/staff, and chocolate. Now,whenever I turn my house-key in the frontdoor lock I have to sneak a peek at Marsover my shoulder. Still there. Doesn’t reallyfeel like an alien planet anymore. Morelike a fellow conspirator, bringing all thoseworkaday people out at odd hours to lookinto space and wonder.As I complete this article, the NorthSaskatchewan River valley is alive withcolour and a fiery promise for the renewalof our earthly greens and blues. Marslingers as a dusky terracotta disc, maybenot as mysterious now that we know somuch more about it, but I find the factseven more fascinating. After the 2003opposition Mars is a closer companionin the mind of the public. Ideas liketerraforming and the current missionswere hot topics during the event. As wegain more knowledge about the diversityof space and persistence of life’s struggle,science has more opportunity to affectthe course of human history in the universe.This is reliant on public awareness andinterest. Will we be part of an uncommonfuture with our close companion? ThisMars event may have played a small partin enabling future exploration of our solarsystem.We’ll be waiting for the next closeencounter. Come “by” us another round,Mars...Sherrilyn Jahrig is Edmonton Centre’s PublicEducation Director and works summers asan Odyssium Observatory operator. Althoughcosmology and deep-sky objects are herpreferred focus, the Solar System seems torule her daily life.RASC INTERNET RESOURCESVisit the RASC Web site Renew your Membership Contact the National Officewww.rasc.ca www.store.rasc.ca nationaloffice@rasc.caJoin the RASC’s email Discussion ListThe RASCals list is a forum for discussion among members of the RASC. The forum encourages communication among members across the countryand beyond. It began in November 1995 and currently has about 300 members.To join the list, send an email to listserv@ap.stmarys.ca with the words “subscribe rascals Your Name (Your Centre)” as the first line of themessage. For further information see: www.rasc.ca/computer/rasclist.htmDecember/ décembre 2003 JRASC295

Reviews of PublicationsCritiques d’ouvragesSolar System Voyage, by Serge Brunier,pages 248 + 0, 25.5 cm × 36 cm. CambridgeUniversity Press, 2003. Price $40 UShardcover (ISBN 0-521-80724-7).It is always interesting to review coffeetablebooks, as they are usually chock fullof interesting photographs. Solar SystemVoyage is no exception, but in a way mostof the book was anticlimactic for me. Oneof the first photographs, of a distantastronaut in a Manned Maneuvering Unit,set against a black sky and hovering overthe Earth, was awfully hard to top! Someimages were enlarged too much and appearquite grainy, but most of the images areextremely sharp. That may originate inpart from thick paper stock, so thick thatit took a while before I stopped trying toseparate two pages that I thought werestuck together!The book is divided into chapterslike those you would find in an introductoryastronomy text, starting with the Sunand working outwards to Pluto. Thereare a few exceptions, such as separatechapters for Phobos and Deimos, Gaspra,Comet Shoemaker-Levy 9, and Triton.Comet Halley gets its own chapter, situatedbetween those of Uranus and Neptune.Titan also gets its own chapter despitethe fact that its few images all look likean orange tennis ball! The rest of Saturn’smoons are forced to share a chapter. TheJupiter system suffers a similar oddity;Io gets its own chapter, while the otherthree Galilean satellites are put togetherinto one.Most chapters begin with a doublepagephotograph of the chapter’s topic.The text begins with a description of whatit would be like to be on the surface ofthe object about to be discussed. You canimagine that you are standing there,surveying the terrain while your spacesuitstruggles to maintain livable conditionsagainst a hostile world. The romanticprose then turns into a fairly detailedscientific examination of the body,something I was not expecting. Sometimesthe text discusses a fact from a point ofview not normally seen, and makes onepause to reflect. A discussion of the Apollomissions states that “these footprints willremain in the lunar soil for millions ofyears, perhaps long after the species thatleft them has disappeared.”While many of the images that gracethe pages of Solar System Voyage arefamiliar to most amateur astronomers,there are bound to be some that the readerwill not have seen before. That is especiallytrue of the chapter on Earth, where imagesof mountains in Nepal and of the GrandCanyon, even with no objects in the pictureto give a sense of measure, show the beautyof the Earth on the grandest of scales.The chapter on Mars sports a wonderfulimage of the Red Planet from the Viking 2orbiter with a black blob on one side ofthe image: Phobos seen in silhouette.Another amazing image is that of M101,with its spiral arms and most of the starfield embedded in the blue tail of CometHyakutake.Given that so many of the imageshave had their colours enhanced bycomputer processing, I was disappointedto find no “disclaimer” warning readersthat the colours in many of the imagesare not what one would see if they wereactually there looking at the objects. Thepictures of Mercury, for example, are allblack-and-white images sent back byMariner 10, yet they are tinted orangered.While it does give a much betterimpression of the planet as being parchedand baked, at first glance it would be easyto mistake them for pictures of Mars. Io’scolouring is even more extreme; in someimages it look like a mouldy orange.Strangely, the caption for an image ofUranus does mention that the brightnessof the rings and moons had been increasedto make them visible.The book concludes with an appendixthat contains a wide variety of information,covering topics such as planetarycartography, telescopes, how best toobserve the planet, and eclipses. Thereare also tables of data about the planetsand moons, major planetary spacemissions, and upcoming eclipses. Theeclipse tables show the book’s Europeanorigins, having a special column for“Visibility in Europe.”There are some errors that detractfrom the book, but many would gounnoticed by a non-astronomer. Page 18states that since the Big Bang the Universehas undergone “constant expansion”;“continual” might be a better adjective.As the book was originally written inFrench, that slip may have been one oftranslation. Others cannot be explainedso easily. A list of stars, all supposedly100,000 times more luminous than theSun, includes stars ranging from Bellatrix(M V = –2.8) to Deneb (M V = –7.5), abrightness ratio of almost 100. A statementthat the Sun’s energy output has beenconstant over the last four billion yearsappears on page 29. Mars suffers two slips:page 86 claims that the stars visible fromthe surface of Mars “do not… form thefamiliar animals and mythical beasts,”and later in the chapter it is stated that“the wind doesn’t affect anything,” incontradiction to earlier statements aboutthe wind being the cause of dust storms.Particularly annoying is a seriousproduction error in the chapter on Europa,Ganymede, and Callisto. While the pagenumbers are in the correct order, thecontents of the pages were accidentally296JRASC December / décembre 2003

transposed so that the order in whichthey have to be read to make sense is 144,145, 149, 147, 146, 148, and 150.Despite the errors, the book does awonderful job of charting our solar system,and I would not hesitate to give it to apassing alien as a photographic souvenirof its visit to our little corner of the MilkyWay.Patrick KellyPatrick Kelly is currently the first vice-presidentof the Halifax Centre and an assistant editorof the Journal.The Bible andAstronomy: TheMagi and the Starin the Gospel, byGustav Teres, S.J., pages340 + xvi; 14 cm × 22cm, Solum Forlag A.S.,Oslo, 2002. Price $39.00US softcover (ISBN 82-560-1341-9).The mystery surrounding the Star ofBethlehem and whether or not there wasan actual celestial signal at the time ofthe birth of Jesus has been the subject ofcountless books and articles. Gustav Tereshas added one more text to the long listof discourses on the subject, but one that,unlike many of its predecessors, is wellgrounded in both astronomy and biblicalscience. In the process the author presentsa very solid case for his own favouriteinterpretation of the Christmas Star, onethat has been advocated by manyastronomers for several years now — thetriple conjunction of Jupiter and Saturnin Pisces of 7 BC. Along the way he alsodiscusses a variety of other astronomicalmysteries raised in the scriptures, resolvingeach in a manner befitting someone whois a scientist and active in the churchministry. On the whole, The Bible andAstronomy is a very interesting andeducational book that tackles many ofthe obvious questions that come to mindwhen one reads biblical passages in thelight of current knowledge about scienceand astronomy. I give it a thumbs-upoverall, but with several reservations.There is great deal that is of interestto Christmas Star specialists in The Bibleand Astronomy. For example, Teres refersto triple conjunctions of Jupiter and Saturnby the less frequently used term “greatconjunctions.” The rationale for thatbecomes clear in the text. The greatconjunction of 7 BC must have beenimportant for Babylonian astronomersbecause three separate copies of theplanetary tablet for that year have beenfound. Yet the actual dates for the threeconjunctions of Jupiter and Saturn thatyear are not recorded on the tablets; onlythe reversal points of the planets (wherethey switch from prograde to retrogrademotion, and vice-versa) are noted. Ourpresent fascination with the actual datesof the three conjunctions thereforemisinterprets what the star watchers ofthat era considered important.One of the lesser-known proposalsput forward regarding the Star of Bethlehemis that of Ferrari d’Occhieppo, who manyyears ago noted the interesting alignmentof the zodiacal light with the planetsJupiter and Saturn on the evening ofNovember 12, 7 BC, when the planetsstood together above the southern horizonat the top of the zodiacal light cone inevening twilight, as viewed from Jerusalem.The configuration is viewed as significantwith regard to matching the descriptionof the Star presented by Matthew, but islittle mentioned in most studies of theStar, possibly because the original workwas published in German. Teres deservesa lot of credit for reviving the alignmentin The Bible and Astronomy as his preferredcandidate for the Star. It must have beena spectacular sight in the skies of Palestine.As he also notes, it matches exactly theastronomical description of the Starrecorded in Matthew, once one translatesthe original biblical text into the languageof star watchers.Inevitably any argument regardinga good candidate for the Star of Bethlehemmust answer the fundamental questionof why the event in question was able toprompt the visit by the magi. What possiblereason is there for a group of magi fromMesopotamia to journey to Judaea insearch of a newborn Messiah? The matteris discussed at length by Teres, whoconcludes that they must have been savantsliving in Babylon, rather than simpleastrologers. Among other details, forexample, he notes that the magi broughtgifts for the newborn child but did notcast a birth horoscope. As concluded bymany others previously, Teres also suggeststhat the details of the birth story mustoriginate from Mary.Here are a few more details that onlya knowledgeable astronomer would note.In 7 BC both Jupiter and Saturn were nearperihelion, therefore closer to Earth thannormal when in opposition, and Saturn’srings were also close to being face-onrather than edge-on. Both planets weretherefore near maximum brightness inour sky that year, so would have beenmore prominent objects than otherwise.All of the greatest Jewish feasts other thanPassover and Pentecost also occur in thefall, when Pisces is highest in the sky.These are just a few of the reasons whyTeres prefers a birth date in Novemberof 7 BC.Teres does discuss previous greatconjunctions of Jupiter and Saturn andwhy they are important (although someof the cited dates seem to vary from onesentence to the next). There was a tripleconjunction in Pisces in 861 BC, forexample, in an era close to the birth ofthe prophet Elijah. There was a simpleconjunction of Jupiter and Saturn inSagittarius in 134 AD, during a revolt bythe Jewish rebel Bar Kochba. Jupiter andSaturn were also briefly in conjunctionin Leo in 34 AD, although that seems abit late relative to when Jesus confrontedthe Jewish scribes, as argued by Teres.More importantly, the 30-year orbitalperiod of Saturn can be related to the“age of maturity” for Jewish teachers orpriests. In another section there is adiscussion of six-pointed stars. In short,nothing is considered too trivial to beincluded in The Bible and Astronomy.Many of the discussions in The Bibleand Astronomy involve numbers, althoughnot always in coherent fashion. I havepreviously noted in these pages (JRASC,92, 278-279, 1998) some reasons why theDecember/ décembre 2003 JRASC297

perfect number six (6) permeatesastronomically-based number systems:the 24-hour day, astronomical co-ordinates,divisions of a circle. Teres opened my eyesto a reason why 60 is also an importantnumber: it is divisible by ten differentnumbers (2, 3, 4, 5, 6, 10, 12, 15, 20, 30)without a remainder.What The Bible and Astronomy doeslack is an enlightened discussion of thehistory of that era. Although historicalquestions may not be necessary fordiscussions related to Teres’s preferredcandidate for the Star, concerns aboutsome of the more controversial dates inthe reign of Herod the Great are essentialfor countering other candidates for theStar that have been presented. Teresappears to cite conventional historicaldates as given, despite a variety of currentarguments for revisions to some of them.A lot of very exciting and innovativediscussions have recently been publishedconcerning biblical dates, but none ofthat pervades The Bible and Astronomy.Also missing are detailed remarks aboutthe origin of the relevant books of theNew Testament and the many discrepanciesbetween their accounts.Teres writes in the Preface to theThird Edition of The Bible and Astronomythat readers have commented to him thatthe text “contains some difficult chapters.”I found myself in full agreement withsuch sentiments. The text is very difficultto read, for several reasons. There aremany awkward sentences and paragraphs,perhaps resulting from translationproblems, and the text does not alwaysflow logically from one sentence to thenext, which makes it difficult to followthe train of thought. There are severaltypographical errors that permeate thebook, from frequently generated spellingerrors related to the English homonyms“led” and “lead,” and “past” and “passed,”to punctuation marks that omit themandatory following space. Such typoscreate frequent distractions from thestoryline. Teres also writes in a veryvoluminous style that attempts to includeall pieces of information, howeverextraneous. The text therefore reads muchlike a church sermon in places and becomesvery pedantic for the reader. Much ofwhat is written could be made considerablymore concise without detracting fromthe excellent arguments presented. Itshould not be necessary to read and rereadsections of the text in order to establishwhat is being said. In other places thereader is advised to skim lightly over thewritten text since the main point hasalready been made several times earlier.A good example of a lack of continuityin the text is provided by the followingpassage from Dates in the Vision of Daniel:“To understand these revelations, wemust refer to the history of numbers.The ancient Hebrews and Greeks usedtheir alphabet numerically, having noindependent numeral system. Allnumbers were denoted by letters, andeach word had its own particularnumber. The Hebrew alphabet consistsof twenty-two consonants: Alef = 1 andthe last one, Tau = 400. The Greekalphabet consists of twenty-four letters:Alpha = 1, and the last one, Omega =800.”It took me a bit of head scratching anda visit to the Internet to discover that thecounting system being referred to for theHebrew alphabet goes by ones from 1 to10, then by tens from 10 to 100, andthereafter by hundreds from 100 to 400,or that the Greek number system beingreferred to is similar but contains threeextra symbols, one following omega, thatcount as the numbers 6, 90, and 900. Thereis no explanation for the statements givenin The Bible and Astronomy.Christmas Star specialists will likelybe most interested in the first half of TheBible and Astronomy, which is devotedto a discussion of the Star of Bethlehem.There is one later section on Precessionof the Earth’s Axis and World Eras thatalso pertains directly to the Star and thatraises a very important subject in myview, but most other sections in the lasthalf of the book tend to be extraneous.Teres does discuss a variety of other Biblemysteries, not always successfully. Thesection on Joshua’s Long Day: The Haltingof the Sun presents a generally convincingresolution to a rather absurd and oftenmisinterpretedstatement in the OldTestament, although the supplementarymap is not particularly useful. The sectionon the Cosmic Vision of Ezekiel is moreof a diatribe, however, and begs the obvioussolution, presented by others, of the simplebut rare sighting of a complex pattern ofsolar parhelia. Many following sectionsseem to be little more than articles offaith reiterated for the reader.The last few chapters of The Bibleand Astronomy, on the Galileo Affair andhow faith and science are essentially thesame, could be omitted entirely. Perhapsthey make comforting reading for Churchelders, but the reality is that the CatholicChurch is founded on some rather tenuousprinciples, one being the literal truthbehind statements made in the Bible.That principle was adopted by early popesbut is difficult to reconcile with what weknow about the origin of the various textsof the Bible. Most of the controversies inthe Galileo Affair and in present-dayconflicts between educators andfundamentalists regarding the teachingof evolution in the schools relate to specificstatements made in books of the OldTestament. It is difficult to argue thatthey are “inspired texts” when they provideincomplete records of events that transpiredseveral centuries prior to the ages whenthey were written, according to biblicalscholars. Why Teres spends several chaptersdiscussing such matters is beyond mycomprehension. Perhaps he feels someduty to the Church to espouse principlesthat help to foster the belief that scienceand religion are fundamentally the same.But the text here is not nearly as convincingas in earlier chapters.Many of my complaints about TheBible and Astronomy could easily berectified by running the text throughspelling and grammar check in MicrosoftWord, and although that would not addressthe problem of lack of conciseness, itwould be a good first step. On the basisof its detailed assessment of the manyfactors surrounding the question of theStar of Bethlehem, I am still inclined torecommend the book to others. Be preparedfor a long, tedious read, however, and try298JRASC December / décembre 2003

to avoid reading the last few sectionsentirely.David TurnerDavid Turner is the Review Editor for theJRASC and a member of the Department ofAstronomy and Physics at Saint Mary’sUniversity. He has reviewed several books onthe Christmas Star for the Journal, far toomany for his own sanity, having spent sixyears as a planetarium director/script writerearlier in his career.Parallax: The Race to Measure theCosmos, by Alan W. Hirshfeld, pages 314+ xiii; 15 cm × 24 cm. W.H. Freeman andCo., 2001. Price $23.95 US hardcover (ISBN0-7167-3711-6).The publication of Copernicus’s DeRevolutionibus in 1543 is often consideredto be the fulcrum on which the teetertotterof astronomical history rests. Priorto the “revolution,” opinion solidly favouredan Earth-centred Universe, but the weightof evidence accumulated until the balancetipped in favour of a heliocentric system.As Hirshfeld explains, measurable stellarparallax was originally pursued as anincontestable demonstration that theEarth really did orbit the Sun. But evenbefore astronomers actually detected thetelltale annual wobble in star positions,the motivation for their quest had shiftedto the much broader task of finding howfar away the stars are. Since stellar distancesare the basis for all of astrophysics, asingle pivotal point in the history ofastronomy might better be the firstdefinitive determination of stellar parallaxby Bessel in 1838.Most of Parallax is devoted to thedevelopment of astrometry, or themeasurement of star positions, in thethree centuries between the two significantdates 1543 and 1838. So the subtitle is abit misleading. The “cosmos” does notrefer to more distant stars and galaxies,and events spread out over centuries areonly a “race” for an astronomer! Withinsuch a framework, Hirshfeld weaves awonderful tapestry of tales. At first, manyof them appear to have little to do withthe main narrative, but before long wesee that the threads really do form a broadand elegant picture. How our eyes work,and the problems in fabricating glass,lenses, and precision telescopes addimportant elements to our appreciationof the struggles involved, while issues likeeducation, patronage, and politics remindus how formidable such forces can be inachieving the ultimate goal.Hirshfeld clearly intends his bookto be a popular account. He begins manychapters with cute little stories about hisfather’s influence, his first telescope, hisfirst view of a comet, his experiences atcollege, and so on. For some readers, suchanecdotes may make the book morefriendly, but I found them mildly intrusive.The author does provide references forall his quotes and an extensive bibliography;they add greatly to the book’s value withouttaking away from its appealing and relaxedstyle. (Appropriately, among the citationsis J.D. Fernie’s “The Historical Search forStellar Parallax,” which appeared in threeparts in 1975 in the JRASC.) Nonetheless,there are many undocumented details inHirshfeld’s text, making it clear that it isnot intended to be a truly scholarly treatise.Some examples of unsupported statementsinclude Ibn as-Shatir’s proposal, twocenturies before Copernicus, that eachplanet circles at constant speed in a smallepicycle whose centre moves uniformlyaround the Sun; James Gregory’s idea,put forward in 1663, that the parallax ofMercury might be measured when ittransited the Sun; various biographicaldetails in the lives of many of the characters;the original proponents of the words“satellite” and “telescope”; the allegedrole of Gamma Draconis in the alignmentof Egyptian pyramids; the designer of theLondon monument. I cite these examplesas much to illustrate the wide-rangingterritory that Hirshfeld covers as toillustrate limitations in the references.Like most popular books, Parallaxcontains almost no math, so readers areleft with no real understanding of whythe Astronomical Unit can be determinedby finding the parallax of any one bodyin the solar system. They will also beconfused by the discussion in Chapter 9of how apparent brightness depends ondistance — a discussion that completelyignores the logarithmic response of theeye and erroneously asserts that if a lightbulb appears 1/5th as bright as an identicalbut nearby bulb, it is situated 25 timesfarther away.Nonetheless, I would highlyrecommend Parallax: The Race to Measurethe Cosmos to anyone from high schoolstudent to professional astronomer. Thosewith no previous interest in the historyof science would enjoy the developmentof the plot, the controversies, and theinterplay of the characters, while at thesame time learning a great deal about thescientific process, its frustrations, andits often-unforeseen rewards. For thosewho may think they have heard it allbefore, there are plenty of new twists tothe familiar tales to keep even a specialisteagerly turning to each new chapter.Hirshfeld, himself a professionalastronomer, says in the preface that ashe researched and wrote the book, hecame to know a set of extraordinaryastronomers in a way he never had in hisformal studies. Fortunately for us, he hasshared his findings with eloquence andstyle.Peter BroughtonPeter Broughton is a former President of theRASC and an aficionado of the history ofastronomy.The Big Splat, orHow the MoonCame to Be, byDana McKenzie, 221pages + xi, 23.5 cm ×16.5 cm, John Wiley& Sons, Inc., 2003,Price $38.95 Cdnclothbound (ISBN 0-471-15057-6).Reading astronomy books is one of theprinciple preoccupations of the armchairastronomer. If one lives in Canada’s lightpollutioncapital, it is often the only wayto truly enjoy our hobby when theDecember/ décembre 2003 JRASC299

combined forces of clouds, cold, chiggers,and children keep one away from one’sinstruments. One of the problems withreading too many astronomy books isthe difficulty in finding something trulyexciting and interesting that has not beenpublished before.Dana McKenzie’s new book is oneof those excellent finds. A mathematicianwho has turned his attention to sciencejournalism, McKenzie, in his book TheBig Splat, presents a focused volumethat tells the story of how we havedeveloped the modern theory of theorigin of the Moon (also known as the“Big Whack” hypothesis or moreprosaically as the “giant impacthypothesis”). The story as laid out byMcKenzie shows how both Victorianand modern scientific processes workas he explores the three classical theories(fission, capture, and co-accretion) oflunar origins and contrasts them withthe development of the modern giantimpact theory. The “Big Whack”hypothesis emerged in the mid-1980s ata conference in Kona, Hawaii, wherelunar scientists were asked to focus onthe question of lunar origins. Ratherthan inspiring a fierce debate, theconference attendees found themselvesto be in almost unanimous agreementthat the “Big Whack” hypothesis wasthe only theory that fit the informationbrought back from the Apollo missionsand other lunar probes in the 1960s and‘70s. The “Kona Consensus,” as it becameknown, marked the official debut of thegiant impact hypothesis as the leadingtheory of selenogony (lunar origin) afterseveral false starts.One of the subtexts that runs throughthe book is how lunar science was fairlyneglected throughout much of the 20thcentury. The renaissance in thinking thatcame about as a result of the Apolloprogram provided huge advances inunderstanding for both the Moonresearchers and by extension for planetaryscience in general. The “science payoff ”from the Apollo program is only nowbeing well reported in the popular press.McKenzie does an excellent job ofproducing a well-researched, readable,and exciting account of the developmentof selenogony, and introduces us to anumber of interesting characters alongthe way. In particular, people like GeorgeDarwin (father of the fission hypothesis)and Thomas J.J. See (capture hypothesisproponent) make for interesting reading.Both would be better known today hadtheir hunches turned out to be morecorrect.My one disappointment with thebook is the relative lack of illustration.The mind-boggling violence and explosiveenergy released in the impact betweenEarth and “Theia” (a name for the impactorproposed by Alex Halliday – Theia is themother of Selene the Greek goddess ofthe Moon) is communicated with a fewsmall black and white diagrams showingcomputer models and a few artists’conceptions. Given that Bill Hartmann,the noted space artist, was one of theoriginal proponents of the impact theoryin the 1970s, that is a shame.The impact theory continues to gainmomentum as various issues and concernswith the proposal are eliminated by furtherresearch. Advanced computer modelingcan now generate the Moon with a widevariety of Theias, Earths, impact velocities,and impact angles. Theoretical researchon the origin of the solar system providesa number of mechanisms in whichmigrating planets could set in motionthe chain of events necessary for an impact.The make-up of both the lunar surfaceand the Earth’s mantle appears to beincreasingly consistent with a majorcollision early in Earth’s history, and ofcourse the role and frequency of giantimpacts of all types is much better acceptednow.All in all, McKenzie has done anexcellent job of telling an as yet untoldstory. The tale of the Moon’s origin weavesthrough the tapestry of astronomy fromthe time of Kepler up to 2001, by whichtime computer models of the impact werebeing further refined. The book is anexcellent read both for the scientificdetective work as well as for the well-toldintroduction to planetary science as itexists at the beginning of a new century.It is highly recommended.Denis GreyDenis Grey is a RASC Life Member attachedto the Toronto Centre. He is working on theRASC’s new I. K. Williamson lunar observingcertificate, in part because the Moon is oneof the few things that are easy to see fromdowntown Toronto.300JRASC December / décembre 2003

INDEX TO VOLUME 97, 2003TITLESAbstracts of Papers Presented at the 2003 CASCA Annual MeetingHeld at The University of Waterloo in Waterloo, Ontario,June 1-3, 2003, Oct., 207ALeonid Meteor,Roy Bishop,Jun., 128Canadian Thesis Abstracts, Melvin Blake, Feb., 32, Jun., 132,Dec., 277Fifty Years of Canadian Ph.D.s in Astronomy, Peter Broughton,Feb., 21Heliocentric Conjunctions of Jupiter, Saturn, Uranus, andNeptune, Jim Decandole, Aug., 173January 26, 2001 Fireball and Implications for Meteor VideoCamera Networks, The, Martin Connors, Peter Brown,Douglas P. Hube, Brian Martin, Alister Ling, Donald Hladiuk,Mike Mazur, and Richard Spalding, Dec., 271Millman Fireball Archive, The, Martin Beech, Apr., 71Recollections of a Canadian Astronomer, Donald C. Morton,Feb., 24Variations in 11612-MHz OH Line Emission from IRAS 19566+3423,John Galt, Feb., 15Wideband Photometry of Saturn: 1995-2002, Richard W. Schmude,Jr., Apr., 78AUTHORSAdrian, Terry, Photos Through the Eyepiece, Apr., 107Attas, Michael, Editorial, Dec., 256Attwood, Randy, MOST: Canada’s First Space Telescope Part 2,Feb., 7Auclair, Raymond, La trigonométrie sphérique en astronomie,Aug., 163Auclair, Raymond, Les mesures du temps, Apr., 54Barkhouse, Wayne, Editorial, Feb., 4, Jun., 116, Oct., 192Beech, Martin, Millman Fireball Archive, The, Apr., 71Bishop, Roy, A Leonid Meteor, Jun., 128Blake, R. Melvin, Canadian Thesis Abstracts, Feb., 32, Jun., 132,Dec., 277Bratton, Mark, Scenic Vistas: Cyg-nice!, Jun., 141Scenic Vistas: The Beta/Zeta Arc, Aug., 184Scenic Vistas: The Deeper Sky of Corona Borealis, Apr., 101Broughton, Peter, Fifty Years of Canadian Ph.D.s in Astronomy,Feb., 21Broughton, Peter, What’s in a Name?, Oct., 199Campagnolo, The Hon. Iona, PC, CM, OBC, Lieutenant Governorof British Columbia, Remarks to the 2003 General AssemblyDelegates, Oct., 196Chapman, David M.F., Reflections: J. W. Christy and the Discoveryof Charon, Pluto’s Satellite, Jun., 126Reflections: Maarten Schmidt and the Discovery of QuasarRedshifts, Feb., 13Reflections: Martian Discoveries, Aug., 169Reflections: Meteor Showers and Comets, Oct., 204Reflections: Newtonian Opticks, Dec., 266Reflections: The Astronomer’s Spouse: The UltimateAccessory, Apr., 66Connors, Martin, Kevin A. Douglas, and David A Lyder, ADecade’sProgress in Distance Education Astronomy, Oct., 218Connors, Martin, Peter Brown, Douglas P. Hube, Brian Martin,Alister Ling, Donald Hladiuk, Mike Mazur, and RichardSpalding, The January 26, 2001 Fireball and Implicationsfor Meteor Video Camera Networks, Dec., 271Decandole, Jim, Heliocentric Conjunctions of Jupiter, Saturn,Uranus, and Neptune, Aug., 173Dodd, William, Web Site Reviews, Apr., 87, Jun., 145Dodd, William, What is Sidereal Time and What Is It Good For?,Dec., 278Edgar, James, An Evening with Rajiv Gupta, Aug., 177Enright, Leo, A Tribute to David Levy, Oct., 224Fairbairn, Maxwell B., Computation of Model Asteroid Lightcurves:Practice vs. Theory, Oct., 232Fairbairn, Maxwell B., Photometry of Rotating Planetary TriaxialEllipsoids, Apr., 92Galt, John, Variations in 1612-MHz OH Line Emission from IRAS19566+3423, Feb., 15Gingras, Bruno, Johannes Kepler’s Harmonices mundi: A “Scientific”version of the Harmony of the Spheres, Oct., 228Gingras, Bruno, Johannes Kepler’s Harmonices mundi: A “Scientific”version of the Harmony of the Spheres, Part II, Dec., 259Gupta, Rajiv, President’s Corner, Feb., 2, Apr., 46, Jun., 114, Aug.,150, Oct., 190, Dec., 254Hay, Kim, Society News/Nouvelles de la société, Feb., 40, Apr.,89, Jun., 136, Oct., 223, Dec., 281Hudon, Daniel, Editorial, Apr., 48Jahrig, Sherrilyn, Edmonton’s Amazing Marzathon 2003, Dec.,294Jahrig, Sherrilyn, STS-107, Apr., 108Kaasalainen, Miko, Unveiling Asteroids: International ObservingProject and Amateur-Professional Connection, Dec., 283Mackie, Guy, Draconian Discoveries, Disparities and Doppelgängers,Oct., 225Mackie, Guy, Okanagan Centre Astronomy Contest, Aug., 179McCurdy, Bruce, International Astronomy Day 2004 is SaturdayApril 24, Dec., 282McCurdy, Bruce, Orbital Oddities: Eclipse Flips, Oct., 234Orbital Oddities: Martian Motion I: Zoom In, Apr., 98December/ décembre 2003 JRASC301

Orbital Oddities: Martian Motion II: Zig Zag, Jun., 137Orbital Oddities: Martian Motion III: Zoom Out., Aug.,180Orbital Oddities: Martian Motion IV: The Zeus Effect, Dec.,288Moreau, Suzanne E., Editorial, Aug., 152Morton, Donald C., Recollections of a Canadian Astronomer,Feb., 24Mozel, Philip, Nocturnal Musings Concerning a Winged Horse,Apr., 61Mozel, Philip, The Sky Disk of Nebra, Oct., 245Orenstein, David, Mars in Motion: Keplerian Earth CentredOrbits?, Jun., 13Mars in Motion: Using Vectors to Investigate the RetrogradeLoop, Apr., 82Orenstein, David, Measuring Mars, Feb., 33Percy, John R., Two Good Things About Light Pollution, Feb., 24Pfannenschmidt, Ernest, Boosting Performance by Apodization,Apr., 103Sage, Leslie J., Second Light: Asteroid Spins are Solar Powered,Dec., 268Second Light: Magnetically Powered Gamma-ray Bursts,Jun., 124Second Light: Measuring the Properties of the Universe,Feb., 11Second Light: Pluto’s Expanding Atmosphere, Aug., 171Second Light: Probing the Atmospheres of Extra-SolarPlanets, Apr., 68Second Light: Starburst in a Distant Quasar, Oct., 203Sampson, Russell D., The Visibility of Jupiter During the Day,Jun., 144Schmude, Richard W., Jr., Wideband Photometry of Saturn: 1995-2002, Apr., 78Smith, Frederick R., Awards for Excellence in Astronomy at the2003 Canada Wide Science Fair, Oct., 239Smith, Frederick R., Observation of the 1761 Transit of Venusfrom St. John’s Newfoundland, Dec., 291Waldron, Ron, Astronomy - A Personal Journey, Aug., 186Whitehorne, Mary Lou, Altitude and Limiting Visual Magnitude,Feb., 35Whitehorne, Mary Lou, The Story of Skyways: The RASC’sAstronomy Handbook for Teachers, Dec., 280Young, Scott, The 40th Anniversary of Alouette I - CanadaCelebrates Four Decades in Space, Apr., 90Zimmerman, Brett, Nineteenth-Century American Astronomyand the Sublime, Jun., 120Zimmerman, Brett, The Plurality of Worlds: Nineteenth-CenturyTheories of Extraterrestrials, Aug., 158DEPARTMENTSAcross The RASC40th Anniversary of Alouette I - Canada Celebrates Four Decadesin Space, The, Apr., 90An Evening with Rajiv Gupta, Aug., 177AstroCryptic, Feb., 44, Apr., 112, Jun., 148, Aug., 185, Oct., 238,Dec., 293Astronomy - A Personal Journey, Aug., 186A Tribute to David Levy, Oct., 224Awards for Excellence in Astronomy at the 2003 Canada WideScience Fair, Oct., 239Boosting Performance by Apodization, Apr., 103Draconian Discoveries, Disparities, and Doppelgängers, Oct.,225Edmonton’s Amazing Marzathon 2003, Dec., 294International Astronomy Day 2004 is Saturday April 24, Dec.,282Okanagan Centre Astronomy Contest, Aug., 179Photos Through the Eyepiece, Apr., 107Sky Disk of Nebra, The, Oct., 245Society News/Nouvelles de la société, Feb., 40, Apr., 89, Jun.,136, Oct., 223, Dec., 281STS-107, Apr., 108Visibility of Jupiter During the Day, The, Jun., 144ColumnsOrbital Oddities: Eclipse Flips, Oct., 234Orbital Oddities: Martian Motion I: Zoom In, Apr., 98Orbital Oddities: Martian Motion II: Zig Zag, Jun., 137Orbital Oddities: Martian Motion III: Zoom Out., Aug., 180Orbital Oddities: Martian Motion IV: The Zeus Effect, Dec., 288Reflections: J.W. Christy and the Discovery of Charon, Pluto’sSatellite, Jun., 126Reflections: Maarten Schmidt and the Discovery of QuasarRedshifts, Feb., 13Reflections: Martian Discoveries, Aug., 169Reflections: Meteor Showers and Comets, Oct., 204Reflections: Newtonian Opticks, Dec., 266Reflections: The Astronomer’s Spouse: The Ultimate Accessory,Apr., 66Scenic Vistas: Cyg-nice!, Jun., 141Scenic Vistas: The Beta/Zeta Arc, Aug., 184Scenic Vistas: The Deeper Sky of Corona Borealis, Apr., 101Second Light: Asteroid Spins are Solar Powered, Dec., 268Second Light: Magnetically Powered Gamma-ray Bursts,Jun., 124Second Light: Measuring the Properties of the Universe,Feb., 11Second Light: Pluto’s Expanding Atmosphere, Aug., 171Second Light: Probing the Atmospheres of Extra-Solar Planets,Apr., 68Second Light: Starburst in a Distant Quasar, Oct., 203Correspondence:Apr., 50, Jun., 117, Aug., 154, Dec., 256302JRASC December / décembre 2003

Education NotesA Decade’s Progress in Distance Education Astronomy, Oct.,216Mars in Motion: Keplerian Earth Centred Orbits?, Jun., 133Mars in Motion: Using Vectors to Investigate the RetrogradeLoop, Apr., 82Measuring Mars, Feb, 33,Story of Skyways: the RASC’s Astronomy Handbook for Teachers,The, Dec., 280Web Site Reviews, Apr., 87, Jun., 145What is Sidereal Time and What Is it Good For?, Dec., 278EditorialFeb., 4, Apr., 48, Jun., 116, Aug., 152, Oct., 192, Dec., 256Feature ArticlesAltitude and Limiting Visual Magnitude, Feb., 35Computation of Model Asteroid Lightcurves: Practice vs Theory,Oct., 232Johannes Kepler’s Harmonices mundi: A “Scientific” Version ofthe Harmony of the Spheres, Oct., 228Johannes Kepler’s Harmonices mundi: A“Scientific” Version ofthe Harmony of the Spheres, Part II, Dec., 259La trigonométrie sphérique en astronomie, Aug., 163Les mesures du temps, Apr., 54MOST: Canada’s First Space Telescope Part 2, Feb., 7Nineteenth-Century American Astronomy and the Sublime,Jun., 120Nocturnal Musings Concerning a Winged Horse, Apr., 61Photometry of Rotating Planetary Triaxial Ellipsoids, Apr., 92Plurality of Worlds: Nineteenth-Century Theories of Extraterrestrials,The, Aug., 158Remarks to 2003 General Assembly Delegates, Oct., 196Unveiling Asteroids: International Observing Project andAmateur-Professional Connection, Dec., 283What’s in a Name?, Oct., 199From the PastFeb., 31, Apr., 70, Jun., 127, Aug., 172, Oct., 206, Dec., 270News NotesFeb., 5, Apr., 51, Jun., 118, Aug., 155, Oct., 193, Dec., 257ObituariesRobert Hanbury Brown (1916-2002), Feb., 42, Hugh Noel AlexanderMaclean (1915-2003), Oct., 246, Anne Barbara Underhill(1920-2003), Oct., 247President’s CornerFeb., 2, Apr., 46, Jun., 114, Aug., 150, Oct., 190, Dec., 254Research Papers (see TITLES)Review of PublicationsBible and Astronomy: The Magi and the Star in the Gospel, The,by Gustav Teres, S.J., Dec., 297Big Splat, or How the Moon Came to Be, The, by Dana McKenzie,Dec., 299Celestial Harvest, by James Mullaney, Oct., 249How the Universe Got its Spots: Diary of a Finite Time in a FiniteSpace, by Janna Levin, Apr., 110Mars Observer’s Guide, by Neil Bone, Oct., 250Misfortunes as Blessings in Disguise: The Story of My Life, byDorrit Hoffleit, Jun., 146Parallax: The Race to Measure the Cosmos, by Alan W. Hirshfeld,Dec., 299Solar System Voyages, by Serge Brunier, Dec., 296Star-Crossed Orbits: Inside the U.S.-Russian Space Alliance, byJames Oberg, Apr., 111Star Testing Astronomical Telescopes: A Manuel for OpticalEvaluation and Adjustment, by Harold Richard Suiter, Jun.,147Walter Baade: A Life in Astrophysics, by Donald E. Osterbrock,Apr., 109What Your Astronomy Textbook Won’t Tell You: Clear, SavvyInsights for Mastery, by Normand Sperling, Oct., 249December/ décembre 2003 JRASC303

Great ImagesAuroral Fire and IceHere is a study in contrasts that join the Sun’s energy to Earth’s soil and air. Dark foreground trees point to high thin clouds, which glow like ice backlitby an aurora’s red flames. As the recent solar maximum subsides, these displays will become rarer in the next few years. From the January page ofthe Observer’s Calendar 2004– Photo by Rod Innes304JRASC December / décembre 2003

THE ROYAL ASTRONOMICAL SOCIETY OF CANADANATIONAL OFFICERS AND COUNCIL FOR 2002-2003/CONSEIL ET ADMINISTRATEURS NATIONAUXHonorary PresidentPresident1st Vice-President2nd Vice-PresidentSecretaryTreasurerRecorderLibrarianPast PresidentsEditor of JournalEditor of Observer’s HandbookEditor of Beginner’s Observing GuideEditor of Observer’s CalendarAuthor of SkyWaysRoy Bishop, Ph.D., HalifaxRajiv Gupta, Ph.D., VancouverPeter Jedicke, LondonScott Young, B.Sc., WinnipegKim Hay, KingstonMichael S.F. Watson, Unattached memberHeide Debond, TorontoColin Haig, M.Sc., HamiltonRobert Garrison, Ph.D., Toronto and Randy Attwood, TorontoWayne Barkhouse, Ph.D., HalifaxRajiv Gupta, Ph.D., VancouverLeo Enright, KingstonRajiv Gupta, Ph.D., VancouverMary Lou Whitehorne, AdPR, HalifaxExecutive Secretary Bonnie Bird, M.L.Sc., 136 Dupont Street, Toronto ON M5R 1V2 Telephone: (416) 924-7973CENTRE ADDRESSES/ADRESSES DES CENTRESThe most current contact information and Web site addresses for all Centres are available at the Society’s Web site: www.rasc.caBelleville Centre9 South Park Street, Belleville ON K8P 2W9Okanagan CentrePO Box 20119 TCM, Kelowna BC V1Y 9H2Calgary CentreC/O Calgary Science Centre, PO Box 2100 Station “M”, Calgary AB T2P 2M5Charlottetown CentreC/O Clair Perry, 38 Mt Edward Road, Charlottetown PE C1A 5S2Edmonton CentreC/O Edmonton Space & Science Centre, 11211 – 142 StreetEdmonton AB T5M 4A1Halifax CentrePO Box 31011, Halifax NS B3K 5T9Hamilton CentrePO Box 1223, Waterdown ON L0R 2H0Kingston CentrePO Box 1793, Kingston ON K5L 5J6Kitchener-Waterloo CentreC/O John Beingessner, 479 Cabot Trail, Waterloo ON N2K 3Y3London CentrePO Box 842 Station B, London ON N6A 4Z3Moncton CentreC/O Dr. Francis LeBlanc, Département de physique et d’astronomie,Université de Moncton, Moncton NB E1A 3E9Centre francophone de MontréalCasier postal 206 Station St-Michel, Montréal QC H2A 3L9Montreal CentrePO Box 1752 Station B, Montreal QC H3B 3L3Niagara CentrePO Box 4040, St Catharines ON L2R 7S3Ottawa CentrePO Box 33012, 1974 Baseline Road, Ottawa ON K2C 0E0Prince George Centre7365 Tedford Road, Prince George BC V2N 6S2Centre de Québec2000 boul Montmorency, Québec QC G1J 5E7Regina CentrePO Box 20014 Cornwall Centre, Regina SK S4P 4J7St. John’s CentreC/O Randy Dodge, 206 Frecker Dr, St. John’s NL A1E 5H9Sarnia CentreC/O Jim Selinger, 160 George Street, Sarnia ON N7T 7V4Saskatoon CentrePO Box 317 RPO University, Saskatoon SK S7N 4J8Thunder Bay Centre286 Trinity Crescent, Thunder Bay ON P7C 5V6Toronto CentreC/O Ontario Science Centre, 770 Don Mills Road, Toronto ON M3C 1T3Vancouver CentreC/O The HR Macmillan Space Centre, 1100 Chestnut StreetVancouver BC V6J 3J9Victoria CentreC/O Lauri Roche, 8581 Sentinel Place, Sidney BC V8L 4Z8Windsor CentreC/O Ken Garber, 2831 Alexandra Avenue, Windsor ON N9E 2J8Winnipeg CentrePO Box 2694, Winnipeg MB R3C 4B3

Publications and Products ofThe Royal Astronomical Society of CanadaObserver’s Calendar — 2004This calendar was created by members of the RASC. All photographs weretaken by amateur astronomers using ordinary camera lenses and smalltelescopes and represent a wide spectrum of objects. An informative captionaccompanies every photograph.It is designed with the observer in mind and contains comprehensiveastronomical data such as daily Moon rise and set times, significant lunar andplanetary conjunctions, eclipses, and meteor showers. The 1998, 1999, and 2000editions each won the Best Calendar Award from the Ontario Printing andImaging Association (designed and produced by Rajiv Gupta).Individual Order Prices: $16.95 CDN (members); $19.95 CDN (non-members)$14.95 USD (members); $17.95 USD (non-members)(includes postage and handling; add GST for Canadian orders)The Beginner’s Observing GuideThis guide is for anyone with little or no experience in observing the night sky. Large, easy to read starmaps are provided to acquaint the reader with the constellations and bright stars. Basic information onobserving the Moon, planets and eclipses is provided. There is also a special section to help Scouts,Cubs, Guides, and Brownies achieve their respective astronomy badges.Written by Leo Enright (160 pages of information in a soft-cover book with otabinding that allows thebook to lie flat).Price : $19.95 CDN (Add $3.00 Shipping & Handling; add GST for Canadian orders)Skyways: Astronomy Handbook for TeachersTeaching Astronomy? Skyways Makes it Easy!Written by a Canadian for Canadian teachers and astronomy educators, Skyways is Canadiancurriculum-specific; pre-tested by Canadian teachers; hands-on; interactive; geared for upperelementary, middle school, and junior high grades; fun and easy to use; cost-effective.Skyways is complete with conceptual background; teacher information; student worksheets;resource lists; Canadian contributions to astronomy section FAQ's, and more. Written by Canadianauthor and RASC member, Mary Lou Whitehorne.Price: $16.95 (members); $19.95 (non-members)(includes postage and handling; add GST for Canadian orders)Shop On-Line at www.store.rasc.caSend cheque or money order to: RASC, 136 Dupont St, Toronto ON M5R 1V2 CanadaPlease allow 6-8 weeks for delivery. Orders outside Canada please remit in U.S. Funds.Major credit cards accepted. Call the National Office toll-free at 1-888-924-7272 to place your order.(These products may also be available directly from your local Centre)